WorldWideScience

Sample records for cesium perchlorates

  1. PERCHLORATE FACTS

    Science.gov (United States)

    Perchlorate is an anion (negative ion) with the formula C1O 4-. Perchlorate salts are famous in inorganic chemistry on account of their high solubilities. As a result, they are very difficult to remove. Although hot and concentrated perchloric acid is a strong oxidizing agent,...

  2. Perchlorate isotope forensics

    Science.gov (United States)

    Böhlke, J.K.; Sturchio, N.C.; Gu, B.; Horita, J.; Brown, G.M.; Jackson, W.A.; Batista, J.; Hatzinger, P.B.

    2005-01-01

    Perchlorate has been detected recently in a variety of soils, waters, plants, and food products at levels that may be detrimental to human health. These discoveries have generated considerable interest in perchlorate source identification. In this study, comprehensive stable isotope analyses ( 37Cl/35Cl and 18O/17O/ 16O) of perchlorate from known synthetic and natural sources reveal systematic differences in isotopic characteristics that are related to the formation mechanisms. In addition, isotopic analyses of perchlorate extracted from groundwater and surface water demonstrate the feasibility of identifying perchlorate sources in contaminated environments on the basis of this technique. Both natural and synthetic sources of perchlorate have been identified in water samples from some perchlorate occurrences in the United States by the isotopic method. ?? 2005 American Chemical Society.

  3. Perchlorate in seawater

    Energy Technology Data Exchange (ETDEWEB)

    Martinelango, P. Kalyani [Department of Chemistry and Biochemistry, Texas Tech University, Lubbock, TX 79409-1061 (United States); Tian Kang [Institute of Environmental and Human Health, Texas Tech University, Lubbock, TX 79409 (United States); Dasgupta, Purnendu K. [Department of Chemistry and Biochemistry, Texas Tech University, Lubbock, TX 79409-1061 (United States)]. E-mail: Sandyd@ttu.edu

    2006-05-10

    There has been no reliable published data on the presence of perchlorate in seawater. Seaweeds are among the most important plant life in the ocean and are good sources of iodine and have been widely used as food and nutritional supplement. Perchlorate is known to inhibit the transport of iodide by the sodium iodide symporter (NIS), present e.g., in the thyroid and mammary glands. With perchlorate being increasingly detected in drinking water, milk and various other foods, increasing the iodide intake through inexpensive natural supplements may be an attractive solution for maintaining iodine assimilation. We report here measurable concentrations of perchlorate in several samples of seawater (detectable in about half the samples analyzed). We also report the iodide and perchlorate concentrations of 11 different species of seaweed and the corresponding bioconcentration factors (BCF) for perchlorate and iodide, relative to the seawater from which they were harvested. All seaweed samples came from the same region, off the coast of Northeastern Maine. Concentrations of iodide and perchlorate in four seawater samples collected from the region near harvest time were 30 {+-} 11 and 0.16 {+-} 0.084 {mu}g l{sup -1}, respectively. Concentrations of both iodide and perchlorate varied over a wide range for different seaweed species; iodide ranging from 16 to 3134 mg kg{sup -1} and perchlorate from 0.077 to 3.2 mg kg{sup -1}. The Laminaria species had the highest iodide concentration; Laminaria digitata is the seaweed species most commonly used in the kelp tablets sold in health food stores. Our sample of L. digitata contained 3134 {+-} 15 mg iodide/kg dry weight. The BCF varied widely for different species, with Laminaria species concentrating iodide preferentially over perchlorate. The iodide BCF (BCF{sub i}) to perchlorate BCF (BCF{sub p}) quotient ranged from 0.66 to 53; L. digitata and L. saccarina having a BCF{sub i}/BCF{sub p} value of 45 and 53, respectively, far

  4. Bioelectrical Perchlorate Remediation

    Science.gov (United States)

    Thrash, C.; Achenbach, L. A.; Coates, J. D.

    2007-12-01

    Several bioreactor designs are currently available for the ex-situ biological attenuation of perchlorate- contaminated waters and recently, some of these reactor designs were conditionally approved by the California Department of Health Services for application in the treatment of perchlorate contaminated drinking water. However, all of these systems are dependent on the continual addition of a chemical electron donor to sustain microbial activity and are always subject to biofouling and downstream water quality issues. In addition, residual labile electron donor in the reactor effluent can stimulate microbial growth in water distribution systems and contribute to the formation of potentially toxic trihalomethanes during disinfection by chlorination. As part of our ongoing studies into microbial perchlorate reduction we investigated the ability of dissimilatory perchlorate reducing bacteria (DPRB) to metabolize perchlorate using a negatively charged electrode (cathode) in the working chamber of a bioelectrical reactor (BER) as the primary electron donor. In this instance the DPRB use the electrons on the electrode surface either directly or indirectly in the form of electrolytically produced H2 as a source of reducing equivalents for nitrate and perchlorate reduction. As part of this investigation our fed-batch studies showed that DPRB could use electrons from a graphite cathode poised at -500mV (vs. Ag/AgCl) for the reduction of perchlorate and nitrate. We isolated a novel organism, Dechlorospirillum strain VDY, from the cathode surface after 70 days operation which readily reduced 100 mg.L-1 perchlorate in a mediatorless batch bioelectrical reactor (BER) in 6 days. Continuous up-flow BERs (UFBERs) seeded with active cultures of strain VDY continuously treated waters containing 100 mg.L-1 perchlorate with almost 100% efficiency throughout their operation achieving a non-optimized volumetric loading of 60 mg.L-1 reactor volume.day-1. The same UFBERs also treated

  5. Cesium-137

    International Nuclear Information System (INIS)

    This sheet belongs to a collection which relates to the use of radionuclides essentially in unsealed sources. Its goal is to gather on a single document the most relevant information as well as the best prevention practices to be implemented. These sheets are made for the persons in charge of radiation protection: users, radioprotection-skill persons, labor physicians. Each sheet treats of: 1 - the radio-physical and biological properties; 2 - the main uses; 3 - the dosimetric parameters; 4 - the measurement; 5 - the protection means; 6 - the areas delimitation and monitoring; 7 - the personnel classification, training and monitoring; 8 - the effluents and wastes; 9 - the authorization and declaration administrative procedures; 10 - the transport; and 11 - the right conduct to adopt in case of incident or accident. This sheet deals specifically with Cesium-137

  6. 2-(Benzenesulfonamidopyridinium perchlorate

    Directory of Open Access Journals (Sweden)

    Xun Li

    2009-06-01

    Full Text Available In the title compound, C11H11N2O2S+·ClO4−, the dihedral angle between the benzene and pyridinium rings is 87.33 (10°. An intramolecular N—H...O interaction, with an S=O-bonded O atom as receptor, occurs in the cation. In the crystal structure, ion pairs occur, being linked by strong N—H...O hydrogen bonds. The perchlorate anion plays a further role in the molecular packing by accepting several weak C—H...O interactions.

  7. Perchlorate Reduction by Yeast for Mars Exploration

    Science.gov (United States)

    Sharma, Alaisha

    2015-01-01

    Martian soil contains high levels (0.6 percentage by mass) of calcium perchlorate (Ca(ClO4)2), which readily dissociates into calcium and the perchlorate ion (ClO4-) in water. Even in trace amounts, perchlorates are toxic to humans and have been implicated in thyroid dysfunction. Devising methods to lessen perchlorate contamination is crucial to minimizing the health risks associated with human exploration and colonization of Mars. We designed a perchlorate reduction pathway, which sequentially reduces perchlorate to chloride (Cl-) and oxygen (O2), for implementation in the yeast Saccharomyces cerevisiae. Using genes obtained from perchlorate reducing bacteria Azospira oryzae and Dechloromonas aromatica, we plan to assemble this pathway directly within S. cerevisiae through recombinational cloning. A perchlorate reduction pathway would enable S. cerevisiae to lower perchlorate levels and produce oxygen, which may be harvested or used directly by S. cerevisiae for aerobic growth and compound synthesis. Moreover, using perchlorate as an external electron acceptor could improve the efficiency of redox-imbalanced production pathways in yeast. Although several perchlorate reducing bacteria have been identified and utilized in water treatment systems on Earth, the widespread use of S. cerevisiae as a synthetic biology platform justifies the development of a perchlorate reducing strain for implementation on Mars.

  8. PERCHLORATE CROP INTERACTIONS VIA CONTAMINATED IRRIGATION WATER

    Science.gov (United States)

    Perchlorate has contaminated water and sods at several locations in the United States. Perchlorate is water soluble, exceedingly mobile in aqueous systems, and can persist for many decades under typical ground- and surface water conditions. Perchlorate is of concern because of un...

  9. Organic carbon biostimulates rapid rhizodegradation of perchlorate.

    Science.gov (United States)

    Yifru, Dawit D; Nzengung, Valentine A

    2008-12-01

    Previous hydroponics and field studies identified phytodegradation and rhizodegradation as the two main mechanisms by which plants metabolize perchlorate. Plant uptake and phytodegradation of perchlorate is a slower and undesired process that poses ecological risks resulting from phytoaccumulation of some fraction of the perchlorate. Meanwhile, rhizodegradation is a more rapid and favored process involving perchlorate-degrading bacteria utilizing dissolved organic carbon (DOC) as a carbon and energy (electron) source to rapidly degrade perchlorate to innocuous chloride. In the present study, rhizodegradation of perchlorate by willow trees (Salix nigra) was biostimulated using electron sources obtained from natural and artificial carbon sources. In bioreactors provided with carbon sources as 500 mg/L DOC, 25 to 40 mg/L of initial perchlorate concentrations were removed to below the ion chromatography method detection limit of 2 microg/L in approximately 9 d. For planted controls provided with no electron donors, the time required for the complete removal of the same doses of perchlorate was up to 70 d. Enhancement of rhizodegradation by organic carbon reduced the phytoaccumulated fraction of perchlorate by an order of magnitude from approximately 430 to 20 mg/kg. The implication of the present study is that the high fraction uptake and phytoaccumulation of perchlorate in agricultural products and the recycling of perchlorate into the ecosystem can be significantly curtailed by supplying electron donors derived from organic carbon sources to the root zone of plants. PMID:18593217

  10. Secondary transformation mechanism of paramagnetic centers in irradiated alkali metal perchlorates

    International Nuclear Information System (INIS)

    The EPR method has been used to study thermal transformations of paramagnetic centres (PC) in X-ray irradiated potassium, rubidium and cesium perchlorates. Experimental data make it possible to suppose that diffusion coefficient of O- ion a rather high and this ion is freely diffused already at 262 K. Colliding with [MeClO4]+ centres it is transformed in a molecule of oxygen. Another part of O- is transformed in stable ozonide-ion at 300 K. About room temperature hole centres dissociate with formation of ClO2 radical. It is supposed that part of electron and hole centres is not stabilized but at 77 K it is transformed in stable radiolysis products. This process most effective proceeds in dislocations and on the surface of microcrystals. The suggested model of thermal transformations of primary PC in irradiated perchlorates of alkali metals explains formation of all the finite ion and paramagnetic radiolysis products

  11. Decorporation of cesium-137

    International Nuclear Information System (INIS)

    Cesium radio-isotopes, especially cesium-137 (137Cs) are among the radionuclides of main importance produced by a fission reaction in reactor or a nuclear weapon explosion. In the environment, 137Cs is a major contaminant which can cause severe β, γirradiations and contaminations. 137Cs is distributed widely and relatively uniformly throughout the body with the highest concentration in skeletal muscles. A treatment becomes difficult afterwards. The purposes of this report are Firstly to compare the Prussian blue verses cobalt and potassium ferrocyanide (D.I. blue) efficiency for the 137Cs decorporation and secondly to assess a chronological treatment with D.I. blue. (author)

  12. PERCHLORATE PHYTOREMEDIATION USING HARDWOOD TREES AND VASCULAR PLANTS

    Science.gov (United States)

    Perchlorate has contaminated water and soils at several locations in the United States. Perchlorate iswater soluble, exceedingly mobile in aqueous systems, and can persist for many decades under typical ground and surface water conditions. Perchlorate is of concern because of...

  13. Aripiprazole salts. II. Aripiprazole perchlorate.

    Science.gov (United States)

    Freire, Eleonora; Polla, Griselda; Baggio, Ricardo

    2012-06-01

    The molecular structure of aripiprazole perchlorate (systematic name: 4-(2,3-dichlorophenyl)-1-{4-[(2-oxo-1,2,3,4-tetrahydroquinolin-7-yl)oxy]butyl}piperazin-1-ium perchlorate), C(23)H(28)Cl(2)N(3)O(2)(+)·ClO(4)(-), does not differ substantially from the recently published structure of aripiprazole nitrate [Freire, Polla & Baggio (2012). Acta Cryst. C68, o170-o173]. Both compounds have almost identical bond distances, bond angles and torsion angles. The two different counter-ions occupy equivalent places in the two structures, giving rise to very similar first-order `packing motifs'. However, these elemental arrangements interact with each other in different ways in the two structures, leading to two-dimensional arrays with quite different organizations.

  14. Kinetics for a membrane reactor reducing perchlorate.

    Science.gov (United States)

    Padhye, Lokesh; Rainwater, Ken; Jackson, W Andrew; Morse, Audra

    2007-02-01

    The major objectives of this work were to operate and construct an autohydrogenotrophic reactor and estimate perchlorate degradation kinetics. The results show that autohydrogenotrophic bacteria were cultured in the reactor and capable of removing 3.6 mg/d of perchlorate in the presence of excess hydrogen (99% removal). The reactor was successful in treating the average influent perchlorate concentration of 532 microg/L to the level of 3 microg/L. A first-order relationship was obtained between the concentration of active biomass in the reactor and the hydraulic retention time for the given amount of substrate. During the kinetic loading study, perchlorate removal ranged from 100 to 50%. The kinetic rate of perchlorate degradation observed in this study was 1.62 hr(-1). The significant degradation of perchlorate in these samples indicates the ubiquity of perchlorate-reducing organisms. Additionally, nitrate was simultaneously removed during water treatment (greater than 90% removal). Because of the excess levels of hydrogen, simultaneous removal of nitrate was not believed to significantly affect perchlorate removal. The area of concern was the lack of complete control over biological treatment. The growth of sulfate-reducing organisms in the reactor negatively affected perchlorate removal efficiency. There were no significant effects observed on the dissolved organic carbon and total suspended solids concentration of the effluent, suggesting that the treatment did not produce a large amount of biomass washout.

  15. PHYTOREMEDIATION OF PERCHLORATE BY TOBACCO PLANTS

    Science.gov (United States)

    Previous studies have shown that tobacco plants are tolerant of perchlorate and will accumulate perchlorate in the plant tissues. The objective of this research was to determine the effectiveness of tobacco plants in phytoremediation, a technology that employs plants to degrade,...

  16. ACCUMULATION AND FATE OF PERCHLORATE IN PLANTS

    Science.gov (United States)

    Perchlorate, a component of solid rocket fuels, has emerged as a potential threat to surface water and groundwater at several locations in the U.S. Perchlorate levels up to 16 ug/L were detected in Lake Mead and 5-9 ug/L in the lower Colorado River. The water from the Colorado Ri...

  17. Cesium reservoir and interconnective components

    International Nuclear Information System (INIS)

    The program objective is to demonstrate the technology readiness of a TFE (thermionic fuel element) suitable for use as the basic element in a thermionic reactor with electric power output in the 0.5 to 5.0 MW range. A thermionic converter must be supplied with cesium vapor for two reasons. Cesium atoms adsorbed on the surface of the emitter cause a reduction of the emitter work function to permit high current densities without excessive heating of the emitter. The second purpose of the cesium vapor is to provide space-charge neutralization in the emitter-collector gap so that the high current densities may flow across the gap unattenuated. The function of the cesium reservoir is to provide a source of cesium atoms, and to provide a reserve in the event that cesium is lost from the plasma by any mechanism. This can be done with a liquid cesium metal reservoir in which case it is heated to the desired temperature with auxiliary heaters. In a TFE, however, it is desirable to have the reservoir passively heated by the nuclear fuel. In this case, the reservoir must operate at a temperature intermediate between the emitter and the collector, ruling out the use of liquid reservoirs. Integral reservoirs contained within the TFE will produce cesium vapor pressures in the desired range at typical electrode temperatures. The reservoir material that appears to be the best able to meet requirements is graphite. Cesium intercalates easily into graphite, and the cesium pressure is insensitive to loading for a given intercalation stage. The goals of the cesium reservoir test program were to verify the performance of Cs-graphite reservoirs in the temperature-pressure range of interest to TFE operation, and to test the operation of these reservoirs after exposure to a fast neutron fluence corresponding to seven year mission lifetime. In addition, other materials were evaluated for possible use in the integral reservoir

  18. Perchlorate reduction by microbes inhabiting oil reservoirs

    Science.gov (United States)

    Liebensteiner, Martin; Stams, Alfons; Lomans, Bart

    2014-05-01

    Microbial perchlorate and chlorate reduction is a unique type of anaerobic respiration as during reduction of (per)chlorate chlorite is formed, which is then split into chloride and molecular oxygen. In recent years it was demonstrated that (per)chlorate-reducing bacteria may employ oxygenase-dependent pathways for the degradation of aromatic and aliphatic hydrocarbons. These findings suggested that (per)chlorate may be used as oxygen-releasing compound in anoxic environments that contain hydrocarbons, such as polluted soil sites and oil reservoirs. We started to study perchlorate reduction by microbes possibly inhabiting oil reservoirs. One of the organisms studied was Archaeoglobus fulgidus. This extremely thermophilic archaeon is known as a major contributor to souring in hot oil reservoirs. A. fulgidus turned out to be able to use perchlorate as terminal electron acceptor for growth with lactate (Liebensteiner et al 2013). Genome based physiological experiments indicated that A. fulgidus possesses a novel perchlorate reduction pathway. Perchlorate is first reduced to chlorite, but chlorite is not split into chloride and molecular oxygen as occurs in bacteria. Rather, chlorite reacts chemically with sulfide, forming oxidized sulfur compounds, which are reduced to sulfide in the electron transport chain by the archaeon. The dependence of perchlorate reduction on sulfur compounds could be shown. The implications of our findings as novel strategy for microbiological enhanced oil recovery and for souring mitigation are discussed. Liebensteiner MG, Pinkse MWH, Schaap PJ, Stams AJM and Lomans BP (2013) Archaeal (per)chlorate reduction at high temperature, a matter of abiotic-biotic reactions. Science 340: 85-87

  19. Cesium-137 in biosphere

    International Nuclear Information System (INIS)

    The behaviour of cesium-137 in environment is reviewed. Problems on 137Cs migration in environment, on metabolism andbiological effects are considered. Data on nuclide accumulation in various plants, ways of their entering the man's organism are presented. It is marked that the rate of 137Cs metabolism in the man's organism depends considerably on age, sex, temperature of environment, conditions for activity, water and mineral metabolism and some other factors. It is shown that the annual effective equivalent dose per capita will increase to 2000 yr. up to 1 μSv, that constitutes 0.05% of the average value of irradiation by a natural source

  20. Cesium diffusion in graphite

    Energy Technology Data Exchange (ETDEWEB)

    Evans, R.B. III; Davis, W. Jr.; Sutton, A.L. Jr.

    1980-05-01

    Experiments on diffusion of /sup 137/Cs in five types of graphite were performed. The document provides a completion of the report that was started and includes a presentation of all of the diffusion data, previously unpublished. Except for data on mass transfer of /sup 137/Cs in the Hawker-Siddeley graphite, analyses of experimental results were initiated but not completed. The mass transfer process of cesium in HS-1-1 graphite at 600 to 1000/sup 0/C in a helium atmosphere is essentially pure diffusion wherein values of (E/epsilon) and ..delta..E of the equation D/epsilon = (D/epsilon)/sub 0/ exp (-..delta..E/RT) are about 4 x 10/sup -2/ cm/sup 2//s and 30 kcal/mole, respectively.

  1. The Microbiology of Perchlorate in the Environment

    Science.gov (United States)

    Coates, J. D.

    2007-12-01

    In the last decade perchlorate has been identified as an important groundwater component that poses potential health threat. Although primarily sourced anthropogenically, many recent studies have identified significant natural pools throughout the US and the natural mechanisms of its synthesis remain a mystery. As such, the true perchlorate concentrations naturally present in the environment are still unknown making its regulation problematic. Because of its solubility and non-reactivity the fate and transport of perchlorate in the environment is primarily a function of microbial activity. In the last seven years more than forty specialized perchlorate respiring organisms have been identified and characterized. These dissimilatory perchlorate reducing bacteria (DPRB) are metabolically diverse and environmental populations tend to be dominated by two primary genotypes, the Dechloromonas and the Azospira species. As such, the majority of our understanding of this metabolism is based on these organisms. These organisms are readily found in soil and sedimentary environments and often associate with the rhizosphere. Recent research has demonstrated an accumulation of these organisms along plant roots suggesting their catabolism of root exudates and molecular studies has demonstrated their existence as endophytic infections of the stem and leaves of actively growing Brachypodium grass plants although their exact role under these conditions is unknown. These microorganisms are generally not nutritionally fastidious and vitamin supplementation is unnecessary for growth although molybdenum is a required trace element for perchlorate reduction. The Dechloromonas and Azospira species generally grow optimally at pH values near neutrality in freshwater environments. Even so, recent field studies have shown that related deep-branching members of these genera often predominate in sites of adverse pH or salinity with some species being capable of growth and perchlorate respiration

  2. Perchlorate in The Great Lakes: Isotopic Composition and Origin

    OpenAIRE

    Poghosyan, Armen; Sturchio, Neil C.; Morrison, Candice G.; Beloso, Abelardo D., Jr.; Guan, Yunbin; Eiler, John M.; Jackson, W. Andrew; Hatzinger, Paul B.

    2014-01-01

    Perchlorate is a persistent and mobile contaminant in the environment with both natural and anthropogenic sources. Stable isotope ratios of oxygen (δ^(18)O, Δ^(17)O) and chlorine (δ^(37)Cl) along with the abundance of the radioactive isotope ^(36)Cl were used to trace perchlorate sources and behavior in the Laurentian Great Lakes. These lakes were selected for study as a likely repository of recent atmospheric perchlorate deposition. Perchlorate concentrations in the Great Lakes range from 0....

  3. Environmental biotechnology and microbiology of (per)chlorate reducing bacteria

    NARCIS (Netherlands)

    Mehboob, F.; Schraa, G.; Stams, A.J.M.

    2011-01-01

    Perchlorates are the salts derived from perchloric acid (HClO4). They occur both naturally and through manufacturing. They have been used as a medicine for more than 50 years to treat thyroid gland disorders and are used extensively within the pyrotechnics industry, and ammonium perchlorate is also

  4. PERCHLORATE UPTAKE AND TRANSFORMATION IN AQUATIC PLANTS

    Science.gov (United States)

    Ammonium Perchlorate (AP) is produced on a large scale by the chemical industry, for a wide range of applications for example, as a strong oxidizing agent in solid rocket fuel. AP must be washed out of the inventory periodically due to its limited shelf-life,and replaced with a f...

  5. Cesium transport data for HTGR systems

    International Nuclear Information System (INIS)

    Cesium transport data on the release of cesium from HTGR fuel elements are reviewed and discussed. The data available through 1976 are treated. Equations, parameters, and associated variances describing the data are presented. The equations and parameters are in forms suitable for use in computer codes used to calculate the release of metallic fission products from HTGR fuel elements into the primary circuit. The data cover the following processes: (1) diffusion of cesium in fuel kernels and pyrocarbon, (2) sorption of cesium on fuel rod matrix material and on graphite, and (3) migration of cesium in graphite. The data are being confirmed and extended through work in progress

  6. 3-(Dicyanomethylidene)indan-1-one-Functionalized Calix[4]arene-Calix[4]pyrrole Hybrid: An Ion-Pair Sensor for Cesium Salts.

    Science.gov (United States)

    Yeon, Yerim; Leem, Soojung; Wagen, Corin; Lynch, Vincent M; Kim, Sung Kuk; Sessler, Jonathan L

    2016-09-01

    A chromogenic calix[4]arene-calix[4]pyrrole hybrid ion pair receptor bearing an indane substituent at a β-pyrrolic position has been prepared. On the basis of solution-phase UV-vis spectroscopic analysis and (1)H NMR spectroscopic studies carried out in 10% methanol in chloroform, receptor 1 is able to bind only cesium ion pairs (e.g., CsF, CsCl, and CsNO3) but not the constituent cesium cation (as its perchlorate salt) or the F(-), Cl(-), or NO3(-) anions (as the tetrabutylammonium salts). It thus displays rudimentary AND logic gate behavior. Receptor 1 shows a colorimetric response to cesium ion pairs under conditions of solid-liquid (nitrobenzene) and liquid-liquid (D2O-nitrobenzene-d5) extraction. PMID:27533478

  7. Atmospheric origins of perchlorate on Mars and in the Atacama

    Science.gov (United States)

    Catling, D. C.; Claire, M. W.; Zahnle, K. J.; Quinn, R. C.; Clark, B. C.; Hecht, M. H.; Kounaves, S.

    2010-01-01

    Isotopic studies indicate that natural perchlorate is produced on Earth in arid environments by the oxidation of chlorine species through pathways involving ozone or its photochemical products. With this analogy, we propose that the arid environment on Mars may have given rise to perchlorate through the action of atmospheric oxidants. A variety of hypothetical pathways can be proposed including photochemical reactions, electrostatic discharge, and gas-solid reactions. Because perchlorate-rich deposits in the Atacama desert are closest in abundance to perchlorate measured at NASA's Phoenix Lander site, we made a preliminary study of the means to produce Atacama perchlorate to help shed light on the origin of Martian perchlorate. We investigated gas phase pathways using a 1-D photochemical model. We found that perchlorate can be produced in sufficient quantities to explain the abundance of perchlorate in the Atacama from a proposed gas phase oxidation of chlorine volatiles to perchloric acid. The feasibility of gas phase production for the Atacama provides justification for future investigations of gas phase photochemistry as a possible source for Martian perchlorate.

  8. Perchlorate Exposure and Thyroid Function in Ammonium Perchlorate Workers in Yicheng, China

    Directory of Open Access Journals (Sweden)

    Hongxia Chen

    2014-05-01

    Full Text Available The impact of low level dust on the thyroid function of workers chronically exposed to ammonium perchlorate (AP is uncertain and controversial. The aim of this study was to examine whether workers in China with long-term (>3 years occupational exposure to low levels of AP dust had affected thyroid homeostasis. Mean occupational exposures to AP dust ranged from 0.43 to 1.17 mg/m3. Geometric means of post-shift urinary perchlorate levels were 20.5 µg/L for those exposed and 12.8 µg/L for the controls. No significant differences were found for thyroid function parameters of FT3, FT4, or log TSH or for TPO prevalence or thyroglobulin levels. Additionally, no differences in findings were observed for complete blood count (CBC, serum biochemical profile, or pulmonary function test. Median urinary iodine levels of 172 and 184 µg/L showed that the workers had sufficient iodine intake. This study found no effect on thyroid function from long term, low-level documented exposure to ammonium perchlorate. It is the first study to report both thyroid status parameters and urinary perchlorate, a biomarker of internal perchlorate exposure, in occupationally exposed workers in China.

  9. ACCUMULATION OF PERCHLORATE IN TOBACCO PLANTS: DEVELOPMENT OF A PLANT KINETIC MODEL

    Science.gov (United States)

    Previous studies have shown that tobacco plants are tolerant of perchlorate and will accumulate perchlorate in plant tissues. This research determined the uptake, translocation, and accumulation of perchlorate in tobacco plants. Three hydroponics growth studies were completed u...

  10. Extraction of Perchlorate Using Porous Organosilicate Materials

    Directory of Open Access Journals (Sweden)

    Jenna R. Taft

    2013-04-01

    Full Text Available Sorbent materials were developed utilizing two morphological structures, comprising either hexagonally packed pores (HX or a disordered pore arrangement (CF. The sorbents were functionalized with combinations of two types of alkylammonium groups. When capture of perchlorate by the sorbents was compared, widely varying performance was noted as a result of differing morphology and/or functional group loading. A material providing improved selectivity for perchlorate over perrhenate was synthesized with a CF material using N-trimethoxysilylpropyl-N,N,N-trimethylammonium chloride. Materials were applied in batch and column formats. Binding isotherms followed the behavior expected for a system in which univalent ligands of varying affinity compete for immobilized sites. Performance of the sorbents was also compared to that of commercial Purolite materials.

  11. Decorporation of cesium-137; Decorporation du cesium-137

    Energy Technology Data Exchange (ETDEWEB)

    Le Fleche, Ph.; Destombe, C.; Grasseau, A.; Mathieu, J.; Chancerelle, Y.; Mestries, J.C. [GMR, Direction des Recherches, Etudes et Techniques, 94 - Arcueil (France)

    1997-12-31

    Cesium radio-isotopes, especially cesium-137 ({sup 137}Cs) are among the radionuclides of main importance produced by a fission reaction in reactor or a nuclear weapon explosion. In the environment, {sup 137}Cs is a major contaminant which can cause severe {beta}, {gamma}irradiations and contaminations. {sup 137}Cs is distributed widely and relatively uniformly throughout the body with the highest concentration in skeletal muscles. A treatment becomes difficult afterwards. The purposes of this report are Firstly to compare the Prussian blue verses cobalt and potassium ferrocyanide (D.I. blue) efficiency for the {sup 137}Cs decorporation and secondly to assess a chronological treatment with D.I. blue. (author)

  12. Different Strategies for Biological Remediation of Perchlorate Contaminated Groundwater

    OpenAIRE

    Wang, Yue

    2012-01-01

    Perchlorate (ClO4-) has gained attention recently due to its interference with thyroid gland function. In infants and unborn children, inadequate thyroid hormone production can cause mental retardation and thyroid tumors. Since new perchlorate standards will be proposed in 2013, and if a stricter standard is imposed, cost effective technologies will be in high demand. The overall objective of this research was to evaluate two perchlorate bioremediation strategies using indigenous soil bact...

  13. Atmospheric Production of Perchlorate on Earth and Mars

    Science.gov (United States)

    Claire, M.; Catling, D. C.; Zahnle, K. J.

    2009-12-01

    Natural production and preservation of perchlorate on Earth occurs only in arid environments. Isotopic evidence suggests a strong role for atmospheric oxidation of chlorine species via pathways including ozone or its photochemical derivatives. As the Martian atmosphere is both oxidizing and drier than the driest places on Earth, we propose an atmospheric origin for the Martian perchlorates measured by NASA's Phoenix Lander. A variety of hypothetical formation pathways can be proposed including atmospheric photochemical reactions, electrostatic discharge, and gas-solid reactions. Here, we investigate gas phase formation pathways using a 1-D photochemical model (Catling et al. 2009, accepted by JGR). Because perchlorate-rich deposits in the Atacama desert are closest in abundance to perchlorate measured at NASA's Phoenix Lander site, we start with a study of the means to produce Atacama perchlorate. We found that perchlorate can be produced in sufficient quantities to explain the abundance of perchlorate in the Atacama from a proposed gas phase oxidation of chlorine volatiles to perchloric acid. These results are sensitive to estimated reaction rates for ClO3 species. The feasibility of gas phase production for the Atacama provides justification for further investigations of gas phase photochemistry as a possible source for Martian perchlorate. In addition to the Atacama results, we will present a preliminary study incorporating chlorine chemistry into an existing Martian photochemical model (Zahnle et al. JGR 2008).

  14. Evidence for the distribution of perchlorates on Mars

    Science.gov (United States)

    Clark, Benton C.; Kounaves, Samuel P.

    2016-10-01

    Various Mars missions have detected Cl atoms, chlorides and perchlorates in martian surface materials. The global soils, in particular, always contain significant levels of observable Cl. Direct evidence points to this Cl being in the form of both chlorides and perchlorates, and possibly also chlorates and other oxychlorines. The most widespread measurements have been of Cl atoms, and cannot discern the chemical form. However, from separate evidence of perchlorate obtained at high latitudes (Phoenix lander) and low latitudes (Curiosity rover), it is likely that perchlorates are widespread, albeit in varying proportions relative to the total amount of ubiquitous Cl.

  15. Interaction of perchlorate and trichloroethene bioreductions in mixed anaerobic culture.

    Science.gov (United States)

    Wen, Li-Lian; Yang, Qiang; Zhang, Zhao-Xin; Yi, Yang-Yi; Tang, Youneng; Zhao, He-Ping

    2016-11-15

    This work evaluated the interaction of perchlorate and trichloroethene (TCE), two common co-contaminants in groundwater, during bioreduction in serum bottles containing synthetic mineral salts media and microbial consortia. TCE at concentrations up to 0.3mM did not significantly affect perchlorate reduction; however, perchlorate concentrations higher than 0.1mM made the reduction of TCE significantly slower. Perchlorate primarily inhibited the reduction of vinyl chloride (VC, a daughter product of TCE) to ethene. Mechanistic analysis showed that the inhibition was mainly because perchlorate reduction is thermodynamically more favorable than reduction of TCE and its daughter products and not because of toxicity due to accumulation of dissolved oxygen produced during perchlorate reduction. As the initial perchlorate concentration increased from 0 to 600mg/L in a set of serum bottles, the relative abundance of Rhodocyclaceae (a putatively perchlorate-reducing genus) increased from 6.3 to 80.6%, while the relative abundance of Dehalococcoides, the only known genus that is able to reduce TCE all the way to ethene, significantly decreased. Similarly, the relative abundance of Proteobacteria (a phylum to which most known perchlorate-reducing bacteria belong) increased from 22% to almost 80%. PMID:27449607

  16. Perchlorate in the Great Lakes: isotopic composition and origin.

    Science.gov (United States)

    Poghosyan, Armen; Sturchio, Neil C; Morrison, Candice G; Beloso, Abelardo D; Guan, Yunbin; Eiler, John M; Jackson, W Andrew; Hatzinger, Paul B

    2014-10-01

    Perchlorate is a persistent and mobile contaminant in the environment with both natural and anthropogenic sources. Stable isotope ratios of oxygen (δ(18)O, Δ(17)O) and chlorine (δ(37)Cl) along with the abundance of the radioactive isotope (36)Cl were used to trace perchlorate sources and behavior in the Laurentian Great Lakes. These lakes were selected for study as a likely repository of recent atmospheric perchlorate deposition. Perchlorate concentrations in the Great Lakes range from 0.05 to 0.13 μg per liter. δ(37)Cl values of perchlorate from the Great Lakes range from +3.0‰ (Lake Ontario) to +4.0‰ (Lake Superior), whereas δ(18)O values range from -4.1‰ (Lake Superior) to +4.0‰ (Lake Erie). Great Lakes perchlorate has mass-independent oxygen isotopic variations with positive Δ(17)O values (+1.6‰ to +2.7‰) divided into two distinct groups: Lake Superior (+2.7‰) and the other four lakes (∼+1.7‰). The stable isotopic results indicate that perchlorate in the Great Lakes is dominantly of natural origin, having isotopic composition resembling that measured for indigenous perchlorate from preindustrial groundwaters of the western USA. The (36)Cl/Cl ratio of perchlorate varies widely from 7.4 × 10(-12) (Lake Ontario) to 6.7 × 10(-11) (Lake Superior). These (36)ClO4(-) abundances are consistent with an atmospheric origin of perchlorate in the Great Lakes. The relatively high (36)ClO4(-) abundances in the larger lakes (Lakes Superior and Michigan) could be explained by the presence of (36)Cl-enriched perchlorate deposited during the period of elevated atmospheric (36)Cl activity following thermonuclear bomb tests in the Pacific Ocean. PMID:25171443

  17. Extraction of radioactive cesium from tea leaves

    International Nuclear Information System (INIS)

    Radioactive contamination of foodstuffs attributed to the Fukushima Daiichi nuclear disaster has become a social problem. This study investigated the extraction of radioactive cesium from the contaminated leaves to the tea. The green tea was brewed twice reusing the same leaves to study the difference in extraction of cesium between the first and second brew. Moreover, the extraction of cesium was studied in correlation to brewing time. The concentration of radioactive cesium was determined with gamma spectrometry, and the concentration of caffeine was determined with absorption spectrometry. About 40% of cesium was extracted from leaves in the first brew, and about 80% was extracted in the second brew. The extraction of cesium increased over time, and it reached about 80% after 10 minutes brew. The ratio of radioactive cesium to caffeine decreased linearly over time. This study revealed that the extraction of cesium was higher for the second brew, and a rapid increase in extraction was seen as the tea was brewed for 6 minutes and more. Therefore, the first brew of green tea, which was brewed within 5 minutes, contained the least extraction of radioactive cesium from the contaminated leaves. (author)

  18. High ozone increases soil perchlorate but does not affect foliar perchlorate content

    Science.gov (United States)

    Ozone (O3) is implicated in the natural source inventory of perchlorate (ClO4-), a hydrophilic salt that migrates to ground water and interferes with uptake of iodide in mammals, including humans. Tropospheric O3 is elevated in many areas. We previously showed (Grantz et al., 2013; Environmental Pol...

  19. 76 FR 7762 - Drinking Water: Regulatory Determination on Perchlorate

    Science.gov (United States)

    2011-02-11

    ... Storage in the Thyroid Gland of Human Neonates. J. Pediatric Endocrinology & Metabolism. Vol. 16. p. 521... AGENCY 40 CFR Part 141 RIN 2040-AF08 Drinking Water: Regulatory Determination on Perchlorate AGENCY... the Agency's) regulatory determination for perchlorate in accordance with the Safe Drinking Water...

  20. PERCHLORATE IDENTIFICATION IN FERTILIZERS AND ACCUMULATION IN LETTUCE SEEDLINGS

    Science.gov (United States)

    Perchlorate has contaminated groundwater, drinking water and soils at several locations in the U.S. The primary source of contamination at sites that have been investigated to date seems to be from industrial and military operations that use Perchlorate as an oxidizing agent. How...

  1. Activity of cesium-134 and cesium-137 in game and mushrooms in Poland

    International Nuclear Information System (INIS)

    The activity of cesium-134 and cesium-137 was measured in mushrooms and game in 1986-1991. The samples were collected all over Poland and most of the measurements were carried out for export purposes. The results indicate that the activity ratio of cesium-137 to cesium-134 in some samples is not comparable to that with fallout after the Chernobyl accident. The analysis of some samples of mushrooms from 1985 showed that the activity of cesium-137 was higher compared to any other foodstuff. The level of contamination varied greatly throughout Poland

  2. Bioremediation Potential of Perchlorate Contaminated Deep Vadose Zone

    Science.gov (United States)

    Gal, H.; Ronen, Z.; Weisbrod, N.; Dahan, O.; Nativ, R.

    2007-12-01

    Widespread perchlorate contamination was found in the vadose zone near a plant that manufactures ammonium perchlorate above the coastal aquifer of Israel in Ramat Hasharon. As part of the plant's operations, untreated industrial wastewater was disposed of for over 30 years in unlined wastewater ponds and nearby washes, causing contamination of the unsaturated zone (up to 2200 mg kg-1 sediment at a depth of 20 m) and the groundwater below it (up to 300 mg L-1). In this study, we examined the potential for microbial metabolism of perchlorate reduction in the contaminated deep vadose zone profile by native microbial communities. Microbial reduction of perchlorate was found in three of the four sediment samples taken from different depths. The sediments taken from 1 m (shallowest) and 35 m (deepest- close to the water table) showed the fastest degradation rates, while the sediment taken from 15 m showed the slowest rate. No perchlorate reduction was observed in the sediment taken from 20 m, where perchlorate concentrations were highest. These results were correlated to the viable microorganism counts in the profile. In experiments in which the effect of nitrate was examined, the lag time for perchlorate degradation was found to be inversely correlated to the initial nitrate concentration, while the perchlorate-reduction rates were faster in treatments with higher initial nitrate concentrations. We found no perchlorate degradation as long as nitrate was present in the system: perchlorate reduction was initiated only after all of the nitrate had been reduced. Nitrate-reduction rates were correlated to the initial nitrate concentrations and no lag period was observed. Nitrite was temporarily accumulated during nitrate reduction and was totally reduced, like nitrate, after 4 days. Count of viable microbial communities as well as PCR analysis of the chlorite dismutase gene in the native microbial population exposed to high concentrations of perchlorate (10,000-20,000 mg L-1

  3. Effects of Perchlorate on Organic Molecules under Simulated Mars Conditions

    Science.gov (United States)

    Carrier, B. L.; Kounaves, S. P.

    2014-12-01

    Perchlorate (ClO4-) was discovered in the northern polar region of Mars by the Mars Phoenix Lander in 2008 and has also been recently detected by the Curiosity Rover in Gale Crater [1,2]. Perchlorate has also been shown to be formed under current Mars conditions via the oxidation of mineral chlorides, further supporting the theory that perchlorate is present globally on Mars [3]. The discovery of perchlorate on Mars has raised important questions about the effects of perchlorate on the survival and detection of organic molecules. Although it has been shown that pyrolysis in the presence of perchlorate results in the alteration or destruction of organic molecules [4], few studies have been conducted on the potential effects of perchlorate on organic molecules under martian surface conditions. Although perchlorate is typically inert under Mars-typical temperatures [5], perchlorate does absorb high energy UV radiation, and has been shown to decompose to form reactive oxychlorine species such as chlorite (ClO2-) when exposed to martian conditions including UV or ionizing radiation [6,7]. Here we investigate the effects of perchlorate on the organic molecules tryptophan, benzoic acid and mellitic acid in order to determine how perchlorate may alter these compounds under Mars conditions. Experiments are performed in a Mars Simulation Chamber (MSC) capable of reproducing the temperature, pressure, atmospheric composition and UV flux found on Mars. Soil simulants are prepared consisting of SiO2 and each organic, as well as varying concentrations of perchlorate salts, and exposed in the MSC. Subsequent to exposure in the MSC samples are leached and the leachate analyzed by HPLC and LC-MS to determine the degree of degradation of the original organic and the identity of any potential decomposition products formed by oxidation or chlorination. References: [1] Kounaves et al., J. Geophys. Res. Planets, Vol. 115, p. E00E10, 2010 [2] Glavin et al., J. Geophys. Res. Planets, Vol

  4. Perchlorates as Powerful Catalysts in Many Important Organic Transformations

    Institute of Scientific and Technical Information of China (English)

    G. Bartoli; L. Sambri; M. Locatelli

    2005-01-01

    @@ 1Introduction For long times, metallic perchlorates have been considered dangerous compounds[1] in that they function as explosives and as incontrollable oxidizers. Therefore, the fear of the great hazard connected with their manufacture and uses had prevented an extensive use both in research laboratories and in industrial processes[2].However, recently it has been cleared that this bad reputation is due to the mistaken association of metallic perchlorates with the oxidizing potential of perchloric acid and the pyrotechnic performances of NH4ClO4.

  5. Surface tension of liquid dilute solutions of lead-cesium and bismuth-cesium systems

    International Nuclear Information System (INIS)

    Method of the maximal pressure in a drop was used to measure the surface tension of 15 liquid dilute solutions of lead-cesium system in 0-0.214 at% concentration range and of 12 diluted solutions of bismuth-cesium system in 0-0.160 at.% cesium range from solidification temperature up to 500 dec C. It was found that cesium was characterized as surfactant in lead and bismuth melts. It was established that the temperature coefficient of surface tension changes sufficiently in maximally diluted solutions of alkali metals in bismuth and lead melts. Effect of sodium, potassium, rubidum and cesium on the value of surface tension of lead and bismuth was systematized. Growth of activity in sodium, potassium, rubidium and cesium series was noted

  6. Sorption of cesium on Latvian clays

    International Nuclear Information System (INIS)

    Cesium is like potassium - good solubility and mobile in a ground, easily assimilate in organism expressly brawn woof. It is a problem if pollutant is a radioactive 137Cs. We made experiments to sorption a 2M CsF solution on some Latvian clays which mainly contain hydro micas (cesium content after good elute of clays are in table). We establish, that clay treated with 25 % sulfuric acid adsorb cesium two times more that waste clay. Hereto unstuck elute Cs from clays. (author)

  7. High pressure studies of potassium perchlorate

    Science.gov (United States)

    Pravica, Michael; Wang, Yonggang; Sneed, Daniel; Reiser, Sharissa; White, Melanie

    2016-09-01

    Two experiments are reported on KClO4 at extreme conditions. A static high pressure Raman study was first conducted to 18.9 GPa. Evidence for at least two new phases was observed: one between 2.4 and 7.7 GPa (possibly sluggish), and the second near 11.7 GPa. Then, the X-ray induced decomposition rate of potassium perchlorate (KClO4 → hν KCl + 2O2) was studied up to 15.2 GPa. The time-dependent growth of KCl and O2 was monitored. The decomposition rate slowed at higher pressures. We present the first direct evidence for O2 crystallization at higher pressures, demonstrating that O2 molecules aggregate at high pressure.

  8. The NAS Perchlorate Review: Adverse Effects?

    Energy Technology Data Exchange (ETDEWEB)

    Johnston, Richard B.; Corley, Richard; Cowan, Linda; Utiger, Robert D.

    2005-11-01

    To the editor: Drs. Ginsberg and Rice argue that the reference dose for perchlorate of 0.0007 mg/kg per day recommended by the National Academies’ Committee to Assess the Health Implications of Perchlorate Ingestion is not adequately protective. As members of the committee, we disagree. Ginsberg and Rice base their conclusion on three points. The first involves the designation of the point of departure as a NOEL (no-observed-effect level) versus a LOAEL (lowest-observed-adverse- effect level). The committee chose as its point of departure a dose of perchlorate (0.007 mg/kg per day) that when given for 14 days to 7 normal subjects did not cause a significant decrease in the group mean thyroid iodide uptake (Greer et al. 2002). Accordingly, the committee considered it a NOEL. Ginsberg and Rice focus on the fact that only 7 subjects were given that dose, and they 1seem to say that attention should be paid only to the results in those subjects in whom there was a 1fall in thyroid iodide uptake, and that the results in those in whom there was no fall or an increase should be ignored. They consider the dose to be a LOAEL because of the fall in uptake in those few subjects. It is important to note that a statistically significant decrease of, for example, 5% or even 10%, would not be biologically important and, more important, would not be sustained. For example, in another study (Braverman et al. 2004), administration of 0.04 mg/kg per day to normal subjects for 6 months had no effect on thyroid iodide uptake when measured at 3 and 6 months, and no effect on serum thyroid hormone or thyrotropin concentrations measured monthly (inspection of Figure 5A in the paper by Greer et al. suggests that this dose would inhibit thyroid iodide uptake by about 25% if measured at 2 weeks). The second issue involves database uncertainty. In clinical studies, perchlorate has been administered prospectively to 68 normal subjects for 2 weeks to 6 months. In one study (Brabant et al. 1992

  9. Perchlorate Reductase Is Distinguished by Active Site Aromatic Gate Residues.

    Science.gov (United States)

    Youngblut, Matthew D; Tsai, Chi-Lin; Clark, Iain C; Carlson, Hans K; Maglaqui, Adrian P; Gau-Pan, Phonchien S; Redford, Steven A; Wong, Alan; Tainer, John A; Coates, John D

    2016-04-22

    Perchlorate is an important ion on both Earth and Mars. Perchlorate reductase (PcrAB), a specialized member of the dimethylsulfoxide reductase superfamily, catalyzes the first step of microbial perchlorate respiration, but little is known about the biochemistry, specificity, structure, and mechanism of PcrAB. Here we characterize the biophysics and phylogeny of this enzyme and report the 1.86-Å resolution PcrAB complex crystal structure. Biochemical analysis revealed a relatively high perchlorate affinity (Km = 6 μm) and a characteristic substrate inhibition compared with the highly similar respiratory nitrate reductase NarGHI, which has a relatively much lower affinity for perchlorate (Km = 1.1 mm) and no substrate inhibition. Structural analysis of oxidized and reduced PcrAB with and without the substrate analog SeO3 (2-) bound to the active site identified key residues in the positively charged and funnel-shaped substrate access tunnel that gated substrate entrance and product release while trapping transiently produced chlorate. The structures suggest gating was associated with shifts of a Phe residue between open and closed conformations plus an Asp residue carboxylate shift between monodentate and bidentate coordination to the active site molybdenum atom. Taken together, structural and mutational analyses of gate residues suggest key roles of these gate residues for substrate entrance and product release. Our combined results provide the first detailed structural insight into the mechanism of biological perchlorate reduction, a critical component of the chlorine redox cycle on Earth.

  10. Determination of Perchlorate in Bottled Water from Italy

    Directory of Open Access Journals (Sweden)

    Patrizia Iannece

    2013-06-01

    Full Text Available Perchlorate is regarded as an emerging persistent inorganic contaminant. It is widely known that perchlorate is an endocrine disruptor as it competitively inhibits iodide transport in the thyroid gland. As drinking water is the major source of human exposure to perchlorate, its occurrence in commercially available bottled waters purchased in different regions of Italy was investigated. Perchlorate was measured using the rapid, sensitive, and selective LC-ESI-MS/MS (liquid chromatography-electrospray tandem mass spectrometry method by multiple reaction monitoring (MRM of the transition 98.8→82.8, which corresponds to the loss of one oxygen atom in the perchlorate ion (ClO4−→ClO3−. The chlorine isotope ratio (35Cl/37Cl was used as a confirmation tool. The limit of quantification (LOQ for this method was 5 ng/L, and the recovery ranged from 94% to 108%. Perchlorate was detected in 44 of the 62 drinking waters tested, with concentrations ranging from <5 to 75 ng/L. These values are similar in magnitude to those reported in drinking water from the USA and do not pose an immediate health concern.

  11. Cesium and strontium ion specific exchangers

    Energy Technology Data Exchange (ETDEWEB)

    Yates, S.

    1996-10-01

    This work is one of two parallel projects that are part of an ESP task to develop high-capacity, selective, solid extractants for cesium, strontium, and technetium from nuclear wastes. In this subtask, Pacific Northwest National Laboratory (PNNL) is collaborating with AlliedSignal, Inc. (Des Plaines, Illinois) to develop inorganic ion exchangers that are selective for strontium and cesium from alkaline high-level waste and groundwater streams.

  12. Sorption of Cesium on Latvia clays

    International Nuclear Information System (INIS)

    Cesium is like potassium - good solubility and mobile in a ground, easy assimilates in organism expressly brawn woof. It is a problem if pollutant is radioactive 137Cs. We made experiments to sorption a 2M CsF solution on some Latvian clays which mainly contain hydro micas. We establish that clay treated with 25% sulfuric acid absorb cesium two times more that waste clay. Hereto unstuck elute Cs from clays

  13. Thermal and Evolved Gas Analysis of Magnesium Perchlorate: Implications for Perchlorates in Soils at the Mars Phoenix Landing Site

    Science.gov (United States)

    Ming, Douglas W.; Morris, R.V.; Lauer, H. V.; Sutter, B.; Golden, D.C.; Boynton, W.V.

    2009-01-01

    Perchlorate salts were discovered in the soils around the Phoenix landing site on the northern plains of Mars [1]. Perchlorate was detected by an ion selective electrode that is part of the MECA Wet Chemistry Laboratory (WCL). The discovery of a mass 32 fragment (likely 02) by the Thermal and Evolved-Gas Analyzer (TEGA) provided additional confirmation of a strong oxidizer in the soils around the landing site. The purpose of this paper is to evaluate the thermal and evolved gas behavior of perchlorate salts using TEGA-like laboratory testbed instruments. TEGA ovens were fabricated from high purity Ni. Hence, an additional objective of this paper is to determine the effects that Ni might have on the evolved gas behavior of perchlorate salts.

  14. Removal of cesium from wastewater: A cesium-specific ion exchange resin

    International Nuclear Information System (INIS)

    Researchers at the Savannah River Laboratory (SRL) have applied for a patent for an ion exchange resin that will remove cesium from water. Radioactive cesium-137 is a fission product of nuclear reactor operations. Cesium may enter the water of spent fuel holding basins through defects in fuel cladding. Control of cesium in these basins is desirable to keep personnel exposure to a minimum. Cesium is also present in the waste from reprocessing of defense nuclear reactor fuel. Research has been underway at SRL for over a decade to improve management of high-level reprocessing waste. The current technology separates the waste into soluble and insoluble components. Radioactive constituents are removed from the soluble component stream and combined with the insoluble components, which are then converted to a glass for long-term storage. Cesium is the most radioactive constituent of the soluble components stream. The SRL resin is a resorcinol-formaldehyde condensation polymer highly specific for cesium and is about 10 times more effective in removal of cesium than other ion exchange resins evaluated for use in processing defense nuclear waste. Tests have been run at SRL using both simulated and actual waste streams

  15. Perchlorate in The Great Lakes: Distribution, Isotopic Composition and Origin

    Science.gov (United States)

    Poghosyan, A.; Sturchio, N. C.; Jackson, W. A.; Guan, Y.; Eiler, J. M.; Hatzinger, P. B.

    2013-12-01

    Concentrations, stable chlorine and oxygen isotopic compositions, and 36Cl abundances of perchlorate were investigated in the five Laurentian Great Lakes. Samples were collected during monitoring cruises in 2007 and 2008 of the U.S. EPA's RV Lake Guardian and in 2010 at the water supply intake of Marquette, MI on the southern shore of Lake Superior. Concentrations of perchlorate were measured by IC/MS/MS at 24 locations, including one or two depth profiles in each lake. Mean concentrations (μg/L) are: Superior, 0.06 × 0.01; Michigan, 0.10 × 0.01; Huron, 0.11 × 0.01; Erie, 0.08 × 0.01, and Ontario, 0.09 × 0.01. Concentration vs. depth is nearly constant in each lake, indicating well-mixed conditions. Perchlorate was extracted from near-surface water by passing 15,000 to 80,000 L of water through 1-L cartridges containing Purolite A530E bifunctional anion-exchange resin. In the laboratory, perchlorate was eluted from the resin, purified, and precipitated as a >99% pure crystalline phase. Milligram amounts were recovered from each lake. Chlorine and oxygen isotopic analyses were performed at Caltech using the Cameca 7f-GEO SIMS instrument, following validation of the SIMS method with analyses of USGS-37 and USGS-38 isotopic reference materials. Results indicate a relatively narrow range in δ37Cl values (+2.9 to +3.9 ‰) and a wider range in δ18O values (-4.0 to +4.1 ‰), with a general geographic trend of increasing δ18O from west to east. Oxygen-17 was measured at UIC using dual-inlet IRMS of O2 produced by decomposition of KClO4. Great Lakes perchlorate has mass-independent oxygen isotopic variations with positive Δ17O values (+1.6 ‰ to +2.7 ‰) divided into two distinct groups: Lake Superior (+2.7 ‰) and the other four lakes (~ +1.7 ‰). The isotopic data indicate that perchlorate is dominantly of natural origin, having stable isotopic compositions resembling those of perchlorate from pre-industrial groundwaters in the western USA. The 36Cl

  16. Oxidation of some disubstituted anisole derivatives with ceric perchlorate in perchloric acid solution

    International Nuclear Information System (INIS)

    The influence of concentration of particular reagents on the kinetics of Ce(IV) reduction by 2,6-dimethyl and 3,5-dimethyl-anisole as well as 2-methoxy-5-methyl- and 4-methoxy-2-methyl-aniline in perchloric acid solution was investigated, establishing the stoichiometry of these processes. Some intermediate products - macromolecular, derivatives of p-benzoquinone and 4,4'-diphenoquinone - were separated and identified. The effects of substituents and the conditions of performed oxidation processes on the kind and yields of the resultant products were considered. (author). 22 refs, 1 fig., 1 tab

  17. Perchlorate, iodine supplements, iodized salt and breast milk iodine content

    International Nuclear Information System (INIS)

    This study was undertaken to determine if increasing maternal iodine intake through single dose tablets will decrease breast milk concentrations of the iodine-uptake inhibitor, perchlorate, through competitive inhibition. We also sought to determine if the timing of supplementation influences the fraction of iodine excreted in milk versus urine and to compare the effectiveness of iodized salt as a means of providing iodine to breastfed infants. Thirteen women who did not use supplements, seven of whom used iodized salt and six of whom used non-iodized salt, submitted four milk samples and a 24-h urine collection daily for three days. Women repeated the sampling protocol for three more days during which ∼ 150 μg of iodine were taken in the evening and again for three days with morning supplementation. Samples were analyzed using isotope-dilution inductively-coupled plasma-mass spectrometry for iodine and isotope-dilution ion chromatography-tandem mass spectrometry for perchlorate. No statistically significant differences were observed in milk iodine or perchlorate concentrations during the two treatment periods. Estimated perchlorate intake was above the U.S. National Academy of Sciences suggested reference dose for most infants. Single daily dose iodine supplementation was not effective in decreasing milk perchlorate concentrations. Users of iodized salt had significantly higher iodine levels in milk than non-users. Iodized salt may be a more effective means of iodine supplementation than tablets. - Highlights: ► Estimated infant exposures to perchlorate were, on a μg/kg basis, ∼ 5 × higher than those of mothers. ► Daily supplements are less effective than iodized salt in providing iodine to lactating women. ► Low iodine and high perchlorate in milk may place infants at risk of iodine deficiency.

  18. Perchlorate, iodine supplements, iodized salt and breast milk iodine content

    Energy Technology Data Exchange (ETDEWEB)

    Kirk, Andrea B. [Department of Epidemiology, School of Public Health, University of North Texas Health Sciences Center, 3500 Camp Bowie Blvd., Fort Worth, TX 76107 (United States); Kroll, Martina; Dyke, Jason V.; Ohira, Shin-Ichi; Dias, Rukshan A.; Dasgupta, Purnendu K. [Department of Chemistry and Biochemistry, 700 Planetarium Place, University of Texas at Arlington, Arlington, TX 76019 (United States)

    2012-03-15

    This study was undertaken to determine if increasing maternal iodine intake through single dose tablets will decrease breast milk concentrations of the iodine-uptake inhibitor, perchlorate, through competitive inhibition. We also sought to determine if the timing of supplementation influences the fraction of iodine excreted in milk versus urine and to compare the effectiveness of iodized salt as a means of providing iodine to breastfed infants. Thirteen women who did not use supplements, seven of whom used iodized salt and six of whom used non-iodized salt, submitted four milk samples and a 24-h urine collection daily for three days. Women repeated the sampling protocol for three more days during which {approx} 150 {mu}g of iodine were taken in the evening and again for three days with morning supplementation. Samples were analyzed using isotope-dilution inductively-coupled plasma-mass spectrometry for iodine and isotope-dilution ion chromatography-tandem mass spectrometry for perchlorate. No statistically significant differences were observed in milk iodine or perchlorate concentrations during the two treatment periods. Estimated perchlorate intake was above the U.S. National Academy of Sciences suggested reference dose for most infants. Single daily dose iodine supplementation was not effective in decreasing milk perchlorate concentrations. Users of iodized salt had significantly higher iodine levels in milk than non-users. Iodized salt may be a more effective means of iodine supplementation than tablets. - Highlights: Black-Right-Pointing-Pointer Estimated infant exposures to perchlorate were, on a {mu}g/kg basis, {approx} 5 Multiplication-Sign higher than those of mothers. Black-Right-Pointing-Pointer Daily supplements are less effective than iodized salt in providing iodine to lactating women. Black-Right-Pointing-Pointer Low iodine and high perchlorate in milk may place infants at risk of iodine deficiency.

  19. Radioactive cesium in Finnish mushrooms

    International Nuclear Information System (INIS)

    Surveillance of radioactive cesium in Finnish mushrooms was started in 1986 at STUK. Results of the surveillance programs carried out in Lapland and other parts of Finland are given in this report. More than 2000 samples of edible mushrooms have been analysed during 1986-2008. The 137Cs detected in the mushrooms mainly originates from the 137Cs deposition due to the accident at the Chernobyl nuclear power plant in 1986. The 137Cs concentrations of mushrooms in the end of 1970s and in the beginning of 1980s varied from some ten to two hundred becquerels per kilogram originating from the nuclear weapon test period. The uneven division of the Chernobyl fallout is seen in the areal variation of 137Cs concentrations of mushrooms, the 137Cs concentrations being about tenfold in the areas with the highest deposition compared to those where the deposition was lowest. After the Chernobyl accident the maximum values in the 137Cs concentrations were reached during 1987-88 among most species of mushrooms. The 137Cs concentrations have decreased slowly, being in 2008 about 40 per cent of the maximum values. The 137Cs concentrations may be tenfold in the mushroom species with high uptake of cesium (Rozites caperatus, Hygrophorus camarophyllus, Lactarius trivialis) compared to the species with low uptake (Albatrellus ovinus, Leccinum sp.) picked in the same area. The 137Cs contents in certain species of commercial mushrooms in Finland still exceed the maximum permitted level, 600 Bq/kg, recommended to be respected when placing wild game, wild berries, wild mushrooms and lake fish on the market (Commission recommendation 2003/274/Euratom). Therefore, the 137Cs concentrations of mushrooms should be measured before placing them on the market in the areas of the highest 137Cs deposition, except for Albatrellus ovinus, Boletus sp. and Cantharellus cibarius. The 137Cs concentrations of common commercial mushroom species, Cantharellus tubaeformis and Craterellus cornucopioides often

  20. Aluminum-based drinking-water treatment residuals: A novel sorbent for perchlorate removal

    International Nuclear Information System (INIS)

    Perchlorate contamination of aquifers and drinking-water supplies has led to stringent regulations in several states to reduce perchlorate concentrations in water at acceptable levels for human consumption. Several perchlorate treatment technologies exist, but there is significant cost associated with their use, and the majority of them are unable to degrade perchlorate to innocuous chloride. We propose the use of a novel sorbent for perchlorate, i.e. an aluminum-based drinking-water treatment residual (Al-WTR), which is a by-product of the drinking-water treatment process. Perchlorate sorption isotherms (23 ± 1 oC) showed that the greatest amount (65%) of perchlorate removed by the Al-WTR was observed with the lowest initial perchlorate load (10 mg L-1) after only 2 h of contact time. Increasing the contact time to 24 h, perchlorate removal increased from 65 to 76%. A significant correlation was observed between the amounts of perchlorate removed with evolved chloride in solution, suggesting degradation of perchlorate to chloride. - Drinking-water treatment residuals are a low-cost sorbent for perchlorate

  1. PERCHLORATE-CROP INTERACTIONS FROM CONTAMINATED IRRIGATION WATER AND FERTILIZER APPLICATIONS

    Science.gov (United States)

    Perchlorate has contaminated water and soils at several locations in the United States. Perchlorate is water soluble, exceedingly mobile in aqueous systems, and can persist for many decades under typical ground and surface water conditions. Perchlorate is of concern because of un...

  2. Plasma etching of cesium iodide

    International Nuclear Information System (INIS)

    Thick films of cesium iodide (CsI) are often used to convert x-ray images into visible light. Spreading of the visible light within CsI, however, reduces the resolution of the resulting image. Anisotropic etching of the CsI film into an array of micropixels can improve the image resolution by confining light within each pixel. The etching process uses a high-density inductively coupled plasma to pattern CsI samples held by a heated, rf-biased chuck. Fluorine-containing gases such as CF4 are found to enhance the etch rate by an order of magnitude compared to Ar+ sputtering alone. Without inert-gas ion bombardment, however, the CF4 etch becomes self-limited within a few microns of depth due to the blanket deposition of a passivation layer. Using CF4+Ar continuously removes this layer from the lateral surfaces, but the formation of a thick passivation layer on the unbombarded sidewalls of etched features is observed by scanning electron microscopy. At a substrate temperature of 220 deg. C, the minimum ion-bombardment energy for etching is Ei∼50 eV, and the rate depends on Ei1/2 above 65 eV. In dilute mixtures of CF4 and Ar, the etch rate is proportional to the gas-phase density of atomic fluorine. Above 50% CF4, however, the rate decreases, indicating the onset of net surface polymer deposition. These observations suggest that anisotropy is obtained through the ion-enhanced inhibitor etching mechanism. Etching exhibits an Arrhenius-type behavior in which the etch rate increases from ∼40 nm/min at 40 deg. C to 380 nm/min at 330 deg. C. The temperature dependence corresponds to an activation energy of 0.13±0.01 eV. This activation energy is consistent with the electronic sputtering mechanism for alkali halides

  3. Perlite for permanent confinement of cesium

    Science.gov (United States)

    Balencie, J.; Burger, D.; Rehspringer, J.-L.; Estournès, C.; Vilminot, S.; Richard-Plouet, M.; Boos, A.

    2006-06-01

    We present the potential use of expanded perlite, a metastable amorphous hydrated aluminium silicate, as a permanent medium for the long-term confinement of cesium. The method requires simply a loading by mixing an aqueous cesium nitrate solution and expanded perlite at 300 K followed by densification by sintering. The formation of pollucite, CsAlSi2O6, a naturally occurring mineral phase, upon careful heat treatment is demonstrated by X-ray diffraction. Leaching tests on the resulting glass-ceramics reveal a very low Cs departure of 0.5 mg m-2 d-1.

  4. Crystalline silicotitanates for cesium/strontium removal

    Energy Technology Data Exchange (ETDEWEB)

    Brown, N.; Miller, J.; Sherman, J.

    1996-10-01

    A new class of inorganic ion exchangers called crystalline silicotitanates (CST) has been developed that exhibits very high selectivity for cesium and strontium in the highly alkaline radioactive wastes at the Hanford Site and other DOE sites. Tests have also shown that CSTs have high selectivity for cesium in acidic and neutral solutions. The ESP is supporting an effort at Sandia National Laboratories and Texas A & M University to further develop and characterize the important chemical and physical properties that will determine the applicability of CST to radioactive waste treatment at Hanford and other DOE facilities.

  5. Microbial accumulation of uranium, radium, and cesium

    International Nuclear Information System (INIS)

    Diverse microbial species varied considerably in their ability to accumulate uranium, cesium, and radium. Mechanistic differences in uranium uptake by Saccharomyces cerevisiae and Pseudomonas aeruginosa were indicated. S. serevisiae exhibited a slow (hours) surface accumulation of uranium which was subject to environmental factors, while P. aeruginosa accumulated uranium rapidly (minutes) as dense intracellular deposits and did not appear to be affected by environmental parameters. Metabolism was not required for uranium uptake by either organism. Cesium and radium were concentrated to a considerably lesser extent than uranium by the several species tested

  6. Removal of Radioactive Cesium Using Prussian Blue Magnetic Nanoparticles

    Directory of Open Access Journals (Sweden)

    Sung-Chan Jang

    2014-11-01

    Full Text Available Radioactive cesium (137Cs has inevitably become a human concern due to exposure from nuclear power plants and nuclear accident releases. Many efforts have been focused on removing cesium and the remediation of the contaminated environment. In this study, we elucidated the ability of Prussian blue-coated magnetic nanoparticles to eliminate cesium from radioactive contaminated waste. Thus, the obtained Prussian blue-coated magnetic nanoparticles were then characterized and examined for their physical and radioactive cesium adsorption properties. This Prussian blue-coated magnetic nanoparticle-based cesium magnetic sorbent can offer great potential for use in in situ remediation.

  7. Cesium vapor thermionic converter anomalies arising from negative ion emission

    Science.gov (United States)

    Rasor, Ned S.

    2016-08-01

    Compelling experimental evidence is given that a longstanding limit encountered on cesium vapor thermionic energy converter performance improvement and other anomalies arise from thermionic emission of cesium negative ions. It is shown that the energy that characterizes thermionic emission of cesium negative ions is 1.38 eV and, understandably, is not the electron affinity 0.47 eV determined for the photodetachment threshold of the cesium negative ion. The experimental evidence includes measurements of collector work functions and volt-ampere characteristics in quasi-vacuum cesium vapor thermionic diodes, along with reinterpretation of the classic Taylor-Langmuir S-curve data on electron emission in cesium vapor. The quantitative effects of negative ion emission on performance in the ignited, unignited, and quasi-vacuum modes of cesium vapor thermionic converter operation are estimated.

  8. Preliminary assessment of perchlorate in ecological receptors at the Longhorn Army Ammunition Plant (LHAAP), Karnack, Texas.

    Science.gov (United States)

    Smith, P N; Theodorakis, C W; Anderson, T A; Kendall, R J

    2001-10-01

    There have been increasing human health and ecological concerns about ionic perchlorate (ClO4-) since it was detected in drinking water sources in 1997. Perchlorate is known to affect thyroid function, causing subsequent hormone disruption and potential perturbations of metabolic activities. According to current estimates, perchlorate is found in the surface of groundwater of 14 states, including Texas. Longhorn Army Ammunition Plant, located in east central Texas, was a facility historically associated with perchlorate-containing propellants and rocket motors. Subsequently, perchlorate contamination in ground and surface waters at the facility has been reported. Soil, sediment, water, vegetation, and animal tissue samples were collected from several locations within the plant for a preliminary site assessment of perchlorate contamination. Perchlorate concentrations ranged from 555-5,557,000 ppb in vegetation, 811-2038 ppb in aquatic insects, below detection limits (ND) to 207 ppb in fish, ND-580 ppb in frogs, and ND-2328 ppb in mammals. Consistent with our hypothesis, aquatic organisms inhabiting perchlorate-contaminated surface water bodies contained detectable concentrations of perchlorate. Additionally, terrestrial organisms were exposed through pathways not necessarily related to contaminated surface waters. Therefore, these data demonstrate that aquatic and terrestrial species are exposed to perchlorate in the environment. To our knowledge, this represents the first incidence of perchlorate exposure among wild animals reported in the scientific literature.

  9. Competitive microbial reduction of perchlorate and nitrate with a cathode directly serving as the electron donor

    International Nuclear Information System (INIS)

    Microbial reduction of perchlorate with an electrode as the electron donor represents an emerging technology for remediation of perchlorate contamination; it is important to know how perchlorate reduction behaves when nitrate, a co-contaminant of perchlorate is present. We reported that electrons derived from the electrode can be directly transferred to the bacteria with perchlorate or nitrate as the sole electron acceptor. The presence of nitrate, even at the 0.07 mM level, can slow reduction of perchlorate (0.70 mM) as a poised potential of -0.50 V (vs. SCE) was applied to the inoculated cathode. Increasing the concentration of nitrate resulted in a noticeable inhibitory effect on perchlorate reduction. When the nitrate concentration was 2.10 mM, reduction of 0.70 mM perchlorate was totally inhibited. Bacterial community analyses based on 16S rDNA gene analysis with denaturing gradient gel electrophoresis (DGGE) revealed that most of the bacteria newly enriched on the nitrate and/or perchlorate biocathodes were the known electrochemically active denitrifiers, which possibly prefer to reduce nitrate over perchlorate. These results show that nitrate is a more favorable electron acceptor than perchlorate in the bioelectrochemical system where the cathode directly serves as the electron donor

  10. Anomalous wetting of helium on cesium

    International Nuclear Information System (INIS)

    The authors report studies of the anomalous wetting of a cesium substrate by a liquid helium film by means of the technique of third sound. A hysteretic pre-wetting transition is observed as a function of the amount of helium in the experimental cell. 10 refs., 2 figs

  11. Cesium and Strontium Separation Technologies Literature Review

    Energy Technology Data Exchange (ETDEWEB)

    T. A. Todd; T. A. Todd; J. D. Law; R. S. Herbst

    2004-03-01

    Integral to the Advanced Fuel Cycle Initiative (AFCI) Program’s proposed closed nuclear fuel cycle, the fission products cesium and strontium in the dissolved spent nuclear fuel stream are to be separated and managed separately. A comprehensive literature survey is presented to identify cesium and strontium separation technologies that have the highest potential and to focus research and development efforts on these technologies. Removal of these high-heat-emitting fission products reduces the radiation fields in subsequent fuel cycle reprocessing streams and provides a significant short-term (100 yr) heat source reduction in the repository. This, along with separation of actinides, may provide a substantial future improvement in the amount of fuel that could be stored in a geologic repository. The survey and review of the candidate cesium and strontium separation technologies are presented herein. Because the AFCI program intends to manage cesium and strontium together, technologies that simultaneously separate both elements are of the greatest interest, relative to technologies that separate only one of the two elements.

  12. Simultaneous detection of perchlorate and bromate using rapid high-performance ion exchange chromatography-tandem mass spectrometry and perchlorate removal in drinking water.

    Science.gov (United States)

    West, Danielle M; Mu, Ruipu; Gamagedara, Sanjeewa; Ma, Yinfa; Adams, Craig; Eichholz, Todd; Burken, Joel G; Shi, Honglan

    2015-06-01

    Perchlorate and bromate occurrence in drinking water causes health concerns due to their effects on thyroid function and carcinogenicity, respectively. The purpose of this study was threefold: (1) to advance a sensitive method for simultaneous rapid detection of perchlorate and bromate in drinking water system, (2) to systematically study the occurrence of these two contaminants in Missouri drinking water treatment systems, and (3) to examine effective sorbents for minimizing perchlorate in drinking water. A rapid high-performance ion exchange chromatography-tandem mass spectrometry (HPIC-MS/MS) method was advanced for simultaneous detection of perchlorate and bromate in drinking water. The HPIC-MS/MS method was rapid, required no preconcentration of the water samples, and had detection limits for perchlorate and bromate of 0.04 and 0.01 μg/L, respectively. The method was applied to determine perchlorate and bromate concentrations in total of 23 selected Missouri drinking water treatment systems during differing seasons. The water systems selected include different source waters: groundwater, lake water, river water, and groundwater influenced by surface water. The concentrations of perchlorate and bromate were lower than or near to method detection limits in most of the drinking water samples monitored. The removal of perchlorate by various adsorbents was studied. A cationic organoclay (TC-99) exhibited effective removal of perchlorate from drinking water matrices.

  13. Structure of aqueous sodium perchlorate solutions.

    Science.gov (United States)

    General, Ignacio J; Asciutto, Eliana K; Madura, Jeffry D

    2008-12-01

    Salt solutions have been the object of study of many scientists through history, but one of the most important findings came along when the Hofmeister series were discovered. Their importance arises from the fact that they influence the relative solubility of proteins, and solubility is directly related to one of today's holy grails: protein folding. In this work we characterize one of the more-destabilizing salts in the series, sodium perchlorate, by studying it as an aqueous solution at various concentrations ranging from 0.08 to 1.60 mol/L. Molecular dynamics simulations at room temperature permitted a detailed study of the organization of solvent and cosolvent, in terms of its radial distribution functions, along with the study of the structure of hydrogen bonds in the ions' solvation shells. We found that the distribution functions have some variations in their shape as concentration changes, but the position of their peaks is mostly unaffected. Regarding water, the most salient fact is the noticeable (although small) change in the second hydration shell and even beyond, especially for g(O(w)***O(w)), showing that the locality of salt effects should not be restricted to considerations of only the first solvation shell. The perturbation of the second shell also appears in the study of the HB network, where the difference between the number of HBs around a water molecule and around the Na(+) cation gets much smaller as one goes from the first to the second solvation shell, yet the difference is not negligible. Nevertheless, the effect of the ions past their first hydration shell is not enough to make a noticeable change in the global HB network. The Kirkwood-Buff theory of liquids was applied to our system, in order to calculate the activity derivative of the cosolvent. This coefficient, along with a previously calculated preferential binding, allowed us to establish that if a folded AP peptide is immersed in the studied solution, becoming the solute, then

  14. The Impact of Temperature on Anaerobic Biological Perchlorate Treatment

    Science.gov (United States)

    A 20-month pilot-scale study was conducted to examine the impact of temperature on the performance of an anaerobic biological contactor used to treat perchlorate-contaminated water. The contactor was successfully acclimated with indigenous micro-organisms. Influent temperatures...

  15. POLISHING EFFLUENT FROM A PERCHLORATE-REDUCING ANAEROBIC BIOLOGICAL CONTACTOR

    Science.gov (United States)

    The U.S. Environmental Protection Agency undertook at 3 ½ year pilot-scale biological perchlorate treatment study that included two long (311 and 340 days) examinations of anaerobic effluent polishing. The polishing system consisted of hydrogen peroxide addition and aeration, fo...

  16. Nitrate and Perchlorate removal from groundwater by ion exchange

    Energy Technology Data Exchange (ETDEWEB)

    Burge, S; Halden, R

    1999-09-15

    This study was conducted to evaluate the performance of a small scale ion exchange unit (Krudico, Inc of Auborn, IA) for removal of nitrate and perchlorate from groundwater at Lawrence Livermore National Laboratory's Site 300. The unit was able to treat 3,600 gallons of Site 300 groundwater, at an average influent concentration of 100 mg/L NO{sub 3}{sup -} before breakthrough occurred. The unit contained 2.5 ft{sup 3} of Sybron SR-7 resin. Seventy gallons of regeneration waste were generated (water treated to waste ratio of 51:1). The effluent concentration was about 20 mg/L NO{sub 3}{sup -}, which is equivalent to a treatment efficiency of at least 80%. There are several options for implementing this technology at Site 300. A target well, in the 817 area, has been selected. It has a 3 to 4 gpm flow rate, and concentrations of 90 mg/L NO{sub 3}{sup -} and 40 {micro}g/L perchlorate. The different treatment options include ion exchange treatment of nitrate only, nitrate and perchlorate, or perchlorate only. Option 1: For the treatment of nitrate only, this unit will be able to treat 3,700 gallons of water before regeneration is required. If both columns of the ion exchange unit are used, 7,400 gallons could be treated before the columns will need to be regenerated (producing 140 gallons of waste, per cycle or every 1.5 days). The effluent nitrate concentration is expected to be about 17 mg/L. Annual operation and maintenance costs are estimated to be $0.14 per gallon of water treated. Option 2: If only perchlorate is to be removed with ion exchange at the 817 area, a smaller unit should be considered. A 55 gallon canister filled with ion exchange resin should be able to reduce perchlorate concentrations in the groundwater from 40 {micro}g/L to non-detect levels for three years before the resin would need to be replaced. The contaminant-laden resin would be disposed of as hazardous waste. It is not practical to regenerate the resin because of the extreme

  17. Branched polymeric media: Perchlorate-selective resins from hyperbranched polyethyleneimine

    KAUST Repository

    Chen, Dennis P.

    2012-10-02

    Perchlorate (ClO4 -) is a persistent contaminant found in drinking groundwater sources in the United States. Ion exchange (IX) with selective and disposable resins based on cross-linked styrene divinylbenzene (STY-DVB) beads is currently the most commonly utilized process for removing low concentrations of ClO4 - (10-100 ppb) from contaminated drinking water sources. However, due to the low exchange capacity of perchlorate-selective STY-DVB resins (∼0.5-0.8 eq/L), the overall cost becomes prohibitive when treating groundwater with higher concentration of ClO4 - (e.g., 100-1000 ppb). In this article, we describe a new perchlorate-selective resin with high exchange capacity. This new resin was prepared by alkylation of branched polyethyleneimine (PEI) beads obtained from an inverse suspension polymerization process. Batch and column studies show that our new PEI resin with mixed hexyl/ethyl quaternary ammonium chloride exchange sites can selectively extract trace amounts of ClO4 - from a makeup groundwater (to below detection limit) in the presence of competing ions. In addition, this resin has a strong-base exchange capacity of 1.4 eq/L, which is 1.75-2.33 times larger than those of commercial perchlorate-selective STY-DVB resins. The overall results of our studies suggest that branched PEI beads provide versatile and promising building blocks for the preparation of perchlorate-selective resins with high exchange capacity. © 2012 American Chemical Society.

  18. Sample processing method for the determination of perchlorate in milk

    International Nuclear Information System (INIS)

    In recent years, many different water sources and foods have been reported to contain perchlorate. Studies indicate that significant levels of perchlorate are present in both human and dairy milk. The determination of perchlorate in milk is particularly important due to its potential health impact on infants and children. As for many other biological samples, sample preparation is more time consuming than the analysis itself. The concurrent presence of large amounts of fats, proteins, carbohydrates, etc., demands some initial cleanup; otherwise the separation column lifetime and the limit of detection are both greatly compromised. Reported milk processing methods require the addition of chemicals such as ethanol, acetic acid or acetonitrile. Reagent addition is undesirable in trace analysis. We report here an essentially reagent-free sample preparation method for the determination of perchlorate in milk. Milk samples are spiked with isotopically labeled perchlorate and centrifuged to remove lipids. The resulting liquid is placed in a disposable centrifugal ultrafilter device with a molecular weight cutoff of 10 kDa, and centrifuged. Approximately 5-10 ml of clear liquid, ready for analysis, is obtained from a 20 ml milk sample. Both bovine and human milk samples have been successfully processed and analyzed by ion chromatography-mass spectrometry (IC-MS). Standard addition experiments show good recoveries. The repeatability of the analytical result for the same sample in multiple sample cleanup runs ranged from 3 to 6% R.S.D. This processing technique has also been successfully applied for the determination of iodide and thiocyanate in milk

  19. Thyroid function and reproductive success in rodents exposed to perchlorate via food and water.

    Science.gov (United States)

    Smith, Philip N; Severt, Scott A; Jackson, J W Andrew; Anderson, Todd A

    2006-04-01

    The purpose of the present study was to determine if exposure to perchlorate via food items would have effects on mammals similar to those caused by exposure through drinking water at approximately equivalent doses. Prairie voles (Microtus ochrogaster) and deer mice (Peromyscus maniculatus) were used to assess the potential toxicity of perchlorate-contaminated food items. Voles and mice were divided randomly into three treatment groups--perchlorate-contaminated food (PCF), perchlorate-contaminated water (PCW), and control groups--such that each treatment group contained equal numbers of males and females. Rodents in PCF treatment groups were fed chow formulated with soybean plant matter that had been grown with perchlorate-contaminated irrigation water. Individuals in the control and PCF groups were provided distilled/deionized drinking water, whereas the PCW group received drinking water containing sodium perchlorate. Only slight differences among treatment groups were observed in a variety of endpoints, including reproductive success, tissue perchlorate concentrations, thyroid hormone concentrations, and thyroid histology. However, trends observed in the present study suggest that perchlorate exposure via water may result in slightly greater effects than exposure to perchlorate via food. These data and recent reports of perchlorate in a wide variety of food items indicate that exposure via food intake is an important consideration when examining cumulative risk among humans, livestock, and wildlife.

  20. Sensitivity and adaptability of methanogens to perchlorates: Implications for life on Mars

    Science.gov (United States)

    Kral, Timothy A.; Goodhart, Timothy H.; Harpool, Joshua D.; Hearnsberger, Christopher E.; McCracken, Graham L.; McSpadden, Stanley W.

    2016-01-01

    In 2008, the Mars Phoenix Lander discovered perchlorate at its landing site, and in 2012, the Curiosity rover confirmed the presence of perchlorate on Mars. The research reported here was designed to determine if certain methanogens could grow in the presence of three different perchlorate salt solutions. The methanogens tested were Methanothermobacter wolfeii, Methanosarcina barkeri, Methanobacterium formicicum and Methanococcus maripaludis. Media were prepared containing 0%, 0.5%, 1.0%, 2%, 5% and 10% wt/vol magnesium perchlorate, sodium perchlorate, or calcium perchlorate. Organisms were inoculated into their respective media followed by incubation at each organism's growth temperature. Methane production, commonly used to measure methanogen growth, was measured by gas chromatography of headspace gas samples. Methane concentrations varied with species and perchlorate salt tested. However, all four methanogens produced substantial levels of methane in the presence of up to 1.0% perchlorate, but not higher. The standard procedure for growing methanogens typically includes sodium sulfide, a reducing agent, to reduce residual molecular oxygen. However, the sodium sulfide may have been reducing the perchlorate, thus allowing for growth of the methanogens. To investigate this possibility, experiments were conducted where stainless steel nails were used instead of sodium sulfide as the reducing agent. Prior to the addition of perchlorate and inoculation, the nails were removed from the liquid medium. Just as in the prior experiments, the methanogens produced methane at comparable levels to those seen with sodium sulfide as the reductant, indicating that sodium sulfide did not reduce the perchlorate to any significant extent. Additionally, cells metabolizing in 1% perchlorate were transferred to 2%, cells metabolizing in 2% were transferred to 5%, and finally cells metabolizing in 5% were transferred to 10%. All four species produced methane at 2% and 5%, but not 10

  1. Detection of Perchlorate Anion on Functionalized Silver Colloids Using Surface-Enhanced Raman Scattering

    Energy Technology Data Exchange (ETDEWEB)

    Tio, J.; Wang, W.; Gu, B.

    2005-01-01

    Perchlorate anion interferes with the uptake of iodide by the human thyroid gland and consequently disrupts the regulation of metabolism. Chronic exposure to high levels of perchlorate may lead to the formation of thyroid gland tumors. Although the Environmental Protection Agency (EPA) has not set a maximum contaminant level (MCL) for perchlorate, a draft drinking water range of 4-18 ppb based on 2 liter daily consumption of water has been established. The current EPA approved method for detecting perchlorate uses ion chromatography which has a detection limit of ~1ppb and involves lengthy analytical time in the laboratory. A unique combination of the surface-enhanced Raman scattering (SERS) effect and the bifunctional anion exchange resin’s high selectivity may provide an alternative way to detect perchlorate at such low concentrations and with high specificity. SERS, which uses laser excitation of adsorbed perchlorate anions on silver nanoparticles, has been shown to detect perchlorate anions at concentrations as low as 50 ppb. Normal micro-Raman analysis of perchlorate sorbed onto the resin beads has detected an even lower concentration of 10 ppb. In an effort to integrate these two effects, silver nanoparticles were coated with N-trimethoxysilylpropyl-N,N,N-trimethylammonium chloride, a functional group similar to that found on the resin bead, and subsequently inserted into different perchlorate concentration environments. This method has resulted in perchlorate detection down to ~10 ppb and a more consistent detection of perchlorate anion at ~50 ppb than that of earlier methods. As suggested by the direct insertion of functionalized silver colloids into perchlorate samples, this technique may potentially allow for the development of a probe using on-site Raman spectrometry to detect significantly low concentrations of perchlorate in situ rather than in the laboratory.

  2. Relative source contributions for perchlorate exposures in a lactating human cohort

    International Nuclear Information System (INIS)

    Perchlorate is an iodine-uptake inhibitor and common contaminant of food and drinking water. Understanding the amount of perchlorate exposure occurring through non-water sources is essential for accurate estimates of human exposure levels, and establishment of drinking water limits for this pervasive contaminant. The study objective was to determine the amount of perchlorate intake derived from diet rather than water. Subjects provided drinking water samples, detailed fluid-intake records, 24 h urine collections and four milk samples for nine days. Samples were analyzed for perchlorate by isotope dilution ion chromatography–tandem mass spectrometry. Amounts of perchlorate derived from drinking water and dietary sources were calculated for each individual. Water of local origin was found to contribute a minor fraction of perchlorate intake. Estimated fraction intake from drinking water ranged from 0 to 36%. The mean and median dose of perchlorate derived from non-water sources by lactating women was 0.18 μg/kg/day (range: 0.06 to 0.36 μg/kg/day.) Lactating women consumed more fluid (mean 2.424 L/day) than has been assumed in recent risk assessments for perchlorate. The data reported here indicate that lactating women may be exposed to perchlorate through dietary sources at markedly higher levels than estimated previously. Exposures to perchlorate from non-water sources may be higher than recent estimates, including those used to develop drinking water standards. - Highlights: ► Residence in an area with perchlorate-contaminated water may be a poor predictor of exposure. ► Exposures to perchlorate from food are likely underestimated. ► The relative contributions for human perchlorate exposures should be weighted more heavily towards non-water sources

  3. Environmental impacts of perchlorate with special reference to fireworks--a review.

    Science.gov (United States)

    Sijimol, M R; Mohan, Mahesh

    2014-11-01

    Perchlorate is an inorganic anion that is used in solid rocket propellants, fireworks, munitions, signal flares, etc. The use of fireworks is identified as one of the main contributors in the increasing environmental perchlorate contamination. Although fireworks are displayed for entertainment, its environmental costs are dire. Perchlorates are also emerging as potent thyroid disruptors, and they have an impact on the ecology too. Many studies have shown that perchlorate contaminates the groundwater and the surface water, especially in the vicinity of fireworks manufacturing sites and fireworks display sites. The health and ecological impacts of perchlorate released in fireworks are yet to be fully assessed. This paper reviews fireworks as a source of perchlorate contamination and its expected adverse impacts.

  4. Lanthanide doped strontium-barium cesium halide scintillators

    Energy Technology Data Exchange (ETDEWEB)

    Bizarri, Gregory; Bourret-Courchesne, Edith; Derenzo, Stephen E.; Borade, Ramesh B.; Gundiah, Gautam; Yan, Zewu; Hanrahan, Stephen M.; Chaudhry, Anurag; Canning, Andrew

    2015-06-09

    The present invention provides for a composition comprising an inorganic scintillator comprising an optionally lanthanide-doped strontium-barium, optionally cesium, halide, useful for detecting nuclear material.

  5. Surface interactions of cesium and boric acid with stainless steel

    International Nuclear Information System (INIS)

    In this report, the effects of cesium hydroxide and boric acid on oxidized stainless steel surfaces at high temperatures and near one atmosphere of pressure are investigated. This is the first experimental investigation of this chemical system. The experimental investigations were performed using a mass spectrometer and a mass electrobalance. Surfaces from the different experiments were examined using a scanning electron microscope to identify the presence of deposited species, and electron spectroscopy for chemical analysis to identify the species deposited on the surface. A better understanding of the equilibrium thermodynamics, the kinetics of the steam-accelerated volatilizations, and the release kinetics are gained by these experiments. The release rate is characterized by bulk vaporization/gas-phase mass transfer data. The analysis couples vaporization, deposition, and desorption of the compounds formed by cesium hydroxide and boric acid under conditions similar to what is expected during certain nuclear reactor accidents. This study shows that cesium deposits on an oxidized stainless steel surface at temperatures between 1000 and 1200 Kelvin. Cesium also deposits on stainless steel surfaces coated with boric oxide in the same temperature ranges. The mechanism for cesium deposition onto the oxide layer was found to involve the chemical reaction between cesium and chromate. Some revaporization in the cesium hydroxide-boric acid system was observed. It has been found that under the conditions given, boric acid will react with cesium hydroxide to form cesium metaborate. A model is proposed for this chemical reaction

  6. Distribution and retention of cesium in Swedish boreal forest ecosystems

    International Nuclear Information System (INIS)

    The retention and distribution of cesium in forest environments are being studied at three locations in Sweden. The main part of the cesium found in the soil was recovered in horizons rich in organic matter. The cesium was retained in the soil organic matter in a more or less extractable form. As different soil types have a different distribution pattern of organic matter the distribution of cesium will depend on the forest soil type. The clay content in Swedish forest soils is in general low which will mitigate the retention of cesium in the soil mineral horizons. The cesium present in the tree was considered to be an effect of assimilation by the tissues in the canopy as well as by the roots. The redistribution of cesium within the trees was extensive which was considered to be an effect of a high mobility of cesium in the close system of a forest environment. The cesium will remain in the forest environment for a considerable time but can be removed by forest practice, by leaching out of the soil profile or by the radioactive decay. (au)

  7. Sorption of cesium in intact rock

    Energy Technology Data Exchange (ETDEWEB)

    Puukko, E. [Univ. of Helsinki, Dept. of Chemistry (Finland)

    2014-04-15

    The mass distribution coefficient K{sub d} is used in performance assessment (PA) to describe sorption of a radionuclide on rock. The R{sub d} is determined using crushed rock which causes uncertainty in converting the R{sub d} values to K{sub d} values for intact rock. This work describes a method to determine the equilibrium of sorption on intact rock. The rock types of the planned Olkiluoto waste disposal site were T-series mica gneiss (T-MGN), T-series tonalite granodiorite granite gneiss (T-TGG), P-series tonalite granodiorite granite gneiss (P-TGG) and pegmatitic granite (PGR). These rocks contain different amount of biotite which is the main sorbing mineral. The sorption of cesium on intact rock slices was studied by applying an electrical field to speed up migration of cesium into the rock. Cesium is in the solution as a noncomplex cation Cs{sup +} and it is sorbed by ion exchange. The tracer used in the experiments was {sup 134}Cs. The experimental sorption on the intact rock is compared with values calculated using the in house cation exchange sorption model (HYRL model) in PHREEQC program. The observed sorption on T-MGN and T-TGG rocks was close to the calculated values. Two PGR samples were from a depth of 70 m and three samples were from a depth of 150 m. Cesium sorbed more than predicted on the two 70 m PGR samples. The sorption of Cs on the three 150 m PGR samples was small which was consistent with the calculations. The pegmatitic granite PGR has the smallest content of biotite of the four rock types. In the case of P-TGG rock the observed values of sorption were only half of the calculated values. Two kind of slices were cut from P-TGG drill core. The slices were against and to the direction of the foliation of the biotite rims. The sorption of cesium on P-TGG rock was same in both cases. The results indicated that there was no effect of the directions of the electric field and the foliation of biotite in the P-TGG rock. (orig.)

  8. A Potential Mechanism for Perchlorate Formation on Mars: Surface-Radiolysis-Initiated Atmospheric Chemistry

    Science.gov (United States)

    Wilson, Eric; Atreya, Sushil K.; Kaiser, Ralf-Ingo; Mahaffy, Paul

    2016-10-01

    Perchlorate (ClO4–) is prevalent on Earth, and with observations of perchlorate on lunar samples and chondrite meteorites, along with recent observations indicating the presence of perchlorate (ClO4–) in the Martian surface by the Phoenix lander and the Sample Analysis at Mars (SAM) on the Mars Science Laboratory (MSL) rover, it appears that the existence of perchlorate is widespread throughout the solar system. However, the abundance and isotopic composition of Martian perchlorate suggest that the perchlorate formation mechanism on Mars may involve a different path than perchlorate found elsewhere in the solar system. Motivated by this, we employ a one-dimensional chemical model to investigate the viability of perchlorate formation in the atmosphere of Mars, instigated by the radiolysis of the Martian surface by galactic cosmic rays. The surface-atmosphere interaction to produce Martian perchlorate involves the sublimation of chlorine oxides into the atmosphere, through surface radiolysis, and their subsequent synthesis to form perchloric acid (HClO4), followed by surface deposition and mineralization to form surface perchlorates. Considering the chlorine oxide, OClO, we find an OClO surface flux as low as 3.2x107 molecules cm–2 s–1, sublimated into the atmosphere from the surface could produce sufficient HClO4 to explain the perchlorate concentration on Mars, assuming an accumulation depth of 30 cm and integrated over the Amazonian period. Radiolysis provides an efficient pathway for the oxidation of chlorine, bypassing the efficient Cl/HCl recycling mechanism that characterizes HClO4 formation mechanisms proposed for the Earth but not Mars.

  9. 4-(2-Azaniumylethylpiperazin-1-ium bis(perchlorate

    Directory of Open Access Journals (Sweden)

    Mohammad Reza Reisi

    2011-09-01

    Full Text Available In the title compound, C6H17N32+·2ClO4−, the piperazine ring adopts a chair conformation with the ethylammonium fragment occupying an equatorial position. In the crystal, the dications and perchlorate anions are linked through N—H...O hydrogen bonding and weak C—H...O hydrogen bonding into a three-dimensional supramolecular network.

  10. Perchlorate in fish from a contaminated site in east-central Texas

    International Nuclear Information System (INIS)

    Perchlorate, a known thyroid endocrine disruptor, contaminates surface waters near military instillations where solid fuel rocket motors are manufactured or assembled. To assess potential perchlorate exposure to fish and the human population which may feed on them, fish were collected around the Naval Weapons Industrial Reserve Plant in McLennan County, TX, and analyzed for the presence of the perchlorate anion. The sampling sites included Lake Waco and Belton Lake, and several streams and rivers within their watersheds. The general tendency was that perchlorate was only found in a few species sampled, and perchlorate was not detected in every individual within these species. When detected in the fish, perchlorate tissue concentrations were greater than that in the water. This may be due to highly variable perchlorate concentrations in the water coupled with individual-level variation in elimination from the body, or to routes of exposure other than water. - In perchlorate-contaminated lakes and streams, perchlorate is detected infrequently in fish heads, fillets, and whole bodies, but may be detected more often depending on species and seasonal trends, and always at concentrations higher in the fish than in the water

  11. Exposure to perchlorate induces the formation of macrophage aggregates in the trunk kidney of zebrafish and mosquitofish

    Science.gov (United States)

    Capps, T.; Mukhi, S.; Rinchard, J.J.; Theodorakis, C.W.; Blazer, V.S.; Patino, R.

    2004-01-01

    Environmental contamination of ground and surface waters by perchlorate, derived from ammonium perchlorate (AP) and other perchlorate salts, is of increasing concern. Exposure to perchlorate can impair the thyroid endocrine system, which is thought to modulate renal and immune function in vertebrates. This study with zebrafish Danio rerio and eastern mosquitofish Gambusia holbrooki examined the histological effects of perchlorate on the trunk kidney, which in teleosts serves excretory and hemopoietic functions and therefore may be a target of perchlorate effects. Adult zebrafish of both sexes were exposed in the laboratory to waterborne, AP-derived perchlorate at measured concentrations of 18 mg/L for 8 weeks. Adult male mosquitofish were exposed to waterborne sodium perchlorate at measured perchlorate concentrations of 1-92 mg/L for 8 weeks. Control fish were kept in untreated water. The region of the body cavity containing the trunk kidney was processed from each fish for histological analysis. Macrophage aggregates (MAs), possible markers of contaminant exposure or immunotoxic effect, were present in the hemopoietic region of the kidney in both species exposed to perchlorate. The estimated percent area of kidney sections occupied by MAs was greater in zebrafish exposed to perchlorate at 18 mg/L (P kidney is affected by exposure to perchlorate. The concentrations of perchlorate at which the effects were noted are relatively high but within the range reported in some contaminated habitats.

  12. Containerized Wetland Bioreactor Evaluated for Perchlorate and Nitrate Degradation

    Energy Technology Data Exchange (ETDEWEB)

    Dibley, V R; Krauter, P W

    2004-12-02

    The U.S. Department of Energy (DOE) and Lawrence Livermore Laboratory (LLNL) designed and constructed an innovative containerized wetlands (bioreactor) system that began operation in November 2000 to biologically degrade perchlorate and nitrate under relatively low-flow conditions at a remote location at Site 300 known as Building 854. Since initial start-up, the system has processed over 3,463,000 liters of ground water and treated over 38 grams of perchlorate and 148 kilograms of nitrate. Site 300 is operated by the University of California as a high-explosives and materials testing facility supporting nuclear weapons research. The 11-square mile site located in northern California was added to the NPL in 1990 primarily due to the presence of elevated concentrations of volatile organic compounds (VOCs) in ground water. At the urging of the regulatory agencies, perchlorate was looked for and detected in the ground water in 1999. VOCs, nitrate and perchlorate were released into the soil and ground water in the Building 854 area as the result of accidental leaks during stability testing of weapons or from waste discharge practices that are no longer permitted at Site 300. Design of the wetland bioreactors was based on earlier studies showing that indigenous chlorate-respiring bacteria could effectively degrade perchlorate into nontoxic concentrations of chlorate, chlorite, oxygen, and chloride. Studies also showed that the addition of organic carbon would enhance microbial denitrification. Early onsite testing showed acetic acid to be a more effective carbon source than dried leaf matter, dried algae, or milk replacement starter; a nutrient and carbon source used in a Department of Defense phytoremediation demonstration. No inocula were added to the system. Groundwater was allowed to circulate through the bioreactor for three weeks to acclimate the wetland plants and to build a biofilm from indigenous flora. Using solar energy, ground water is pumped into granular

  13. Distillation device supplies cesium vapor at constant pressure

    Science.gov (United States)

    Basiulis, A.; Shefsiek, P. K.

    1968-01-01

    Distillation apparatus in the form of a U tube supplies small amounts of pure cesium vapor at constant pressure to a thermionic converter. The upstream leg of the U tube is connected to a vacuum pump to withdraw noncondensable impurities, the bottom portion serves as a reservoir for the liquid cesium.

  14. Perchlorate in the Hydrologic Cycle - An Overview of Sources and Occurrence

    Science.gov (United States)

    Stonestrom, D. A.; Jackson, W.; Mayer, K.; Orris, G. J.

    2007-12-01

    Perchlorate (ClO4-) in water and food is of concern due to deleterious health affects associated with hypothyroidism. The presence of widespread perchlorate in 0-to-28 ka-old pristine ground water of the Middle Rio Grande Basin (Plummer et al., 2006, ES&T, DOI:10.1021/es051739h), in ground water >1 mile from agricultural activities in the Southern High Plains (Rajagapolan et al., 2006, ES&T, DOI:10.1021/es052155i), and in unsaturated zones throughout the arid and semiarid southwestern United States (Rao et al., 2007, ES&T, DOI:10.1021/es062853i) clearly indicates that perchlorate is a non-exotic component of the hydrologic cycle, at least in dry environments. The natural system has been greatly perturbed in places by human activities. Most anthropogenic inputs are associated with the manufacture and use of explosives and rocket fuel, providing concentrated sources of excess perchlorate to the hydrologic cycle. Perchlorate-containing fertilizers and irrigation provide dispersed sources within and down-gradient from agricultural areas. Natural sources include photochemically mediated reactions involving ozone at the land surface and in the lower atmosphere. A growing body of work indicates that a small, but persistent, meteoric source acting over thousands of years can explain observed accumulations of unsaturated-zone perchlorate in arid regions. In addition to meteoric sources, oxyanions produced during volcanogenic processes can include appreciable amounts of natural perchlorate. Terrestrial plants take up perchlorate in soil water, with some species of xerophytic succulents concentrating the anion to high levels. Similarly, perchlorate in marine plants indicates that perchlorate is part of marine biochemical cycles. Perchlorate-bearing marine sediments of late Tertiary age suggest that perchlorate has been part of global geochemical cycles for millions of years and, furthermore, can be preserved in the subsurface despite the nearly ubiquitous presence of

  15. Portable Amperometric Perchlorate Selective Sensors with Microhole Array-water/organic Gel Interfaces

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Sang Hyuk; Girault, Hubert H.; Lee, Hye Jin [Kyungpook National Univ., Daegu (Korea, Republic of); Kim, Hyungi [Gyeongbuk Technopark, Gyeongsan (Korea, Republic of); Girault, Hubert H. [Ecole Polytechnique Federale de Lausanne, Lausanne (Switzerland)

    2013-09-15

    A novel stick-shaped portable sensing device featuring a microhole array interface between the polyvinylchloride-2-nitrophenyloctylether (PVC-NPOE) gel and water phase was developed for in-situ sensing of perchlorate ions in real water samples. Perchlorate sensitive sensing responses were obtained based on measuring the current changes with respect to the assisted transfer reaction of perchlorate ions by a perchlorate selective ligand namely, bis(dibenzoylmethanato)Ni(II) (Ni(DBM){sub 2}) across the polarized microhole array interface. Cyclic voltammetry was used to characterize the assisted transfer reaction of perchlorate ions by the Ni(DBM){sub 2} ligand when using the portable sensing device. The current response for the transfer of perchlorate anions by Ni(DBM){sub 2} across the micro-water/gel interface linearly increased as a function of the perchlorate ion concentration. The technique of differential pulse stripping voltammetry was also utilized to improve the sensitivity of the perchlorate anion detection down to 10 ppb. This was acquired by preconcentrating perchlorate anions in the gel layer by means of holding the ion transfer potential at 0 mV (vs. Ag/AgCl) for 30 s followed by stripping the complexed perchlorate ion with the ligand. The effect of various potential interfering anions on the perchlorate sensor was also investigated and showed an excellent selectivity over Br{sup -}, NO{sub 2}{sup -}, NO{sub 3}{sup -}, CO{sub 3}{sup 2-}, CH{sub 3}COO{sup -} and SO{sub 4}{sup 2-} ions. As a final demonstration, some regional water samples from the Sincheon river in Daegu city were analyzed and the data was verified with that of ion chromatography (IC) analysis from one of the Korean-certified water quality evaluation centers.

  16. Extraction of radioactive cesium from ash of flammable radioactive material

    International Nuclear Information System (INIS)

    Huge amount of radioactive materials was released by the hydrogen explosion at Fukushima Daiichi Nuclear Power Plant due to the Great East Japan Earthquake on March 11, 2011. Suppression of the volume of radioactive materials stored by decontamination works is strongly required since the preparation of storage places is not easy. We are developing the technology for separation and concentration of radioactive cesium using nano-particle, Prussian blue, as a cesium adsorption material which has a high efficiency and good selectivity. We propose a method in which radioactive cesium is extracted from the ash of flammable materials into the water and the Prussian blue nano-particles are added to the water to collect cesium. The volume of radioactive wastes contaminated by cesium is expected to be cut down with these processes. (J.P.N.)

  17. A combined cesium-strontium extraction/recovery process

    International Nuclear Information System (INIS)

    A new solvent extraction process for the simultaneous extraction of cesium and strontium from acidic nitrate media is described. This process uses a solvent formulation comprised of 0.05 M di-t-butylcyclohexano-18-crown-6 (DtBuCH18C6), 0.1 M Crown 100' (a proprietary, cesium-selective derivative of dibenzo-18-crown-6), 1.2 M tributyl phosphate (TBP), and 5% (v/v) lauryl nitrile in an isoparaffinic hydrocarbon diluent. Distribution ratios for cesium and strontium from 4 M nitric acid are 4.13 and 3.46, respectively. A benchtop batch countercurrent extraction experiment indicates that >98% of the cesium and strontium initially present in the feed solution can be removed in only four extraction stages. Through proper choice of extraction and strip conditions, extracted cesium and strontium can be recovered either together or individually

  18. Plutonium and Cesium Colloid Mediated Transport

    Science.gov (United States)

    Boukhalfa, H.; Dittrich, T.; Reimus, P. W.; Ware, D.; Erdmann, B.; Wasserman, N. L.; Abdel-Fattah, A. I.

    2013-12-01

    Plutonium and cesium have been released to the environment at many different locations worldwide and are present in spent fuel at significant levels. Accurate understanding of the mechanisms that control their fate and transport in the environment is important for the management of contaminated sites, for forensic applications, and for the development of robust repositories for the disposal of spent nuclear fuel and nuclear waste. Plutonium, which can be present in the environment in multiple oxidations states and various chemical forms including amorphous oxy(hydr)oxide phases, adsorbs/adheres very strongly to geological materials and is usually immobile in all its chemical forms. However, when associated with natural colloids, it has the potential to migrate significant distances from its point of release. Like plutonium, cesium is not very mobile and tends to remain adhered to geological materials near its release point, although its transport can be enhanced by natural colloids. However, the reactivity of plutonium and cesium are very different, so their colloid-mediated transport might be significantly different in subsurface environments. In this study, we performed controlled experiments in two identically-prepared columns; one dedicated to Pu and natural colloid transport experiments, and the other to Cs and colloid experiments. Multiple flow-through experiments were conducted in each column, with the effluent solutions being collected and re-injected into the same column two times to examine the persistence and scaling behavior of the natural colloids, Pu and Cs. The data show that that a significant fraction of colloids were retained in the first elution through each column, but the eluted colloids collected from the first run transported almost conservatively in subsequent runs. Plutonium transport tracked natural colloids in the first run but deviated from the transport of natural colloids in the second and third runs. Cesium transport tracked natural

  19. Adsorption of cesium on cement mortar from aqueous solutions

    Energy Technology Data Exchange (ETDEWEB)

    Volchek, Konstantin, E-mail: konstantin.volchek@ec.gc.ca [Emergencies Science and Technology Section, Environment Canada, 335 River Road, Ottawa, Ontario, Canada K1A 0H3 (Canada); Miah, Muhammed Yusuf [Emergencies Science and Technology Section, Environment Canada, 335 River Road, Ottawa, Ontario, Canada K1A 0H3 (Canada); Department of Applied Chemistry and Chemical Technology, Noakhali Science and Technology University (Bangladesh); Kuang, Wenxing; DeMaleki, Zack [Emergencies Science and Technology Section, Environment Canada, 335 River Road, Ottawa, Ontario, Canada K1A 0H3 (Canada); Tezel, F. Handan [Department of Chemical and Biological Engineering, University of Ottawa, 161 Louis-Pasteur, Ottawa, Ontario, Canada K1N 6N5 (Canada)

    2011-10-30

    Highlights: {yields} The adsorption of cesium on cement mortar was investigated in a range of temperatures and cesium concentrations. {yields} The pseudo-second order kinetic model produced a good fit with the experimental kinetic data. {yields} Equilibrium test results correlated well with the Freundlich isotherm adsorption model. {yields} The interaction between cesium ions and cement mortar was dominated by chemical adsorption. - Abstract: The adsorption of cesium on cement mortar from aqueous solutions was studied in series of bench-scale tests. The effects of cesium concentration, temperature and contact time on process kinetics and equilibrium were evaluated. Experiments were carried out in a range of initial cesium concentrations from 0.0103 to 10.88 mg L{sup -1} and temperatures from 278 to 313 K using coupons of cement mortar immersed in the solutions. Non-radioactive cesium chloride was used as a surrogate of the radioactive {sup 137}Cs. Solution samples were taken after set periods of time and analyzed by inductively coupled plasma mass spectroscopy. Depending on the initial cesium concentration, its equilibrium concentration in solution ranged from 0.0069 to 8.837 mg L{sup -1} while the respective surface concentration on coupons varied from 0.0395 to 22.34 {mu}g cm{sup -2}. Equilibrium test results correlated well with the Freundlich isotherm model for the entire test duration. Test results revealed that an increase in temperature resulted in an increase in adsorption rate and a decrease in equilibrium cesium surface concentration. Among several kinetic models considered, the pseudo-second order reaction model was found to be the best to describe the kinetic test results in the studied range of concentrations. The adsorption activation energy determined from Arrhenius equation was found to be approximately 55.9 kJ mol{sup -1} suggesting that chemisorption was the prevalent mechanism of interaction between cesium ions and cement mortar.

  20. Photodimerization and photooxygenation of 9-vinylcarbazole catalyzed by titanium dioxide and magnesium perchlorate

    Institute of Scientific and Technical Information of China (English)

    Hajime; Maeda; Mio; Yamamoto; Hideyuki; Nakagawa; Kazuhiko; Mizuno

    2010-01-01

    Photoreaction of 9-vinylcarbazole in acetonitrile in the presence of titanium dioxide and a catalytic amount of magnesium perchlorate gave 3,6-di(9-carbazolyl)-1,2-dioxane as a photooxygenated product via photodimerization of 9-vinylcarbazole.The photoreaction proceeds via an electron transfer mechanism,where magnesium perchlorate accelerated formation of the photo-oxygenated product.

  1. Archaeal (Per)Chlorate Reduction at High Temperature: An Interplay of Biotic and Abiotic Reactions

    NARCIS (Netherlands)

    Liebensteiner, M.; Pinkse, M.W.H.; Schaap, P.J.; Stams, A.J.M.; Lomans, B.P.

    2013-01-01

    Perchlorate and chlorate anions [(per)chlorate] exist in the environment from natural and anthropogenic sources, where they can serve as electron acceptors for bacteria. We performed growth experiments combined with genomic and proteomic analyses of the hyperthermophile Archaeoglobus fulgidus that s

  2. Perchlorate and halophilic prokaryotes: implications for possible halophilic life on Mars.

    Science.gov (United States)

    Oren, Aharon; Elevi Bardavid, Rahel; Mana, Lily

    2014-01-01

    In view of the finding of perchlorate among the salts detected by the Phoenix Lander on Mars, we investigated the relationships of halophilic heterotrophic microorganisms (archaea of the family Halobacteriaceae and the bacterium Halomonas elongata) toward perchlorate. All strains tested grew well in NaCl-based media containing 0.4 M perchlorate, but at the highest perchlorate concentrations, tested cells were swollen or distorted. Some species (Haloferax mediterranei, Haloferax denitrificans, Haloferax gibbonsii, Haloarcula marismortui, Haloarcula vallismortis) could use perchlorate as an electron acceptor for anaerobic growth. Although perchlorate is highly oxidizing, its presence at a concentration of 0.2 M for up to 2 weeks did not negatively affect the ability of a yeast extract-based medium to support growth of the archaeon Halobacterium salinarum. These findings show that presence of perchlorate among the salts on Mars does not preclude the possibility of halophilic life. If indeed the liquid brines that may exist on Mars are inhabited by salt-requiring or salt-tolerant microorganisms similar to the halophiles on Earth, presence of perchlorate may even be stimulatory when it can serve as an electron acceptor for respiratory activity in the anaerobic Martian environment.

  3. Perchlorate in groundwater: a synoptic survey of "pristine" sites in the coterminous United States.

    Science.gov (United States)

    Parker, David R; Seyfferth, Angelia L; Reese, Brandi Kiel

    2008-03-01

    Perchlorate is widely used as an oxidant in solid rocket propellants and energetic applications, and it has frequently been detected in groundwaters at concentrations relevant to human health. The possibility of naturally occurring perchlorate has only recently received significant attention. Relying primarily on domestic, agricultural, and recreational wells, we utilized a network of volunteers to help collect 326 groundwater samples from across the coterminous United States. Care was taken to avoid known, USEPA-documented sites of perchlorate use or release, as well as perchlorate contamination due to disinfection using hypochlorite. Using IC-ESI-MS and a Cl18O4- internal standard, we achieved a method detection limit (MDL) of 40 ng/L perchlorate and a minimum reporting level (MRL) of 120 ng/L. Of the 326 samples, 147 (45%) were below the MDL, while 42 (13%) were between the MDL and the MRL. Of the 137 samples that could be quantified, most (109) contained 10000 ng/L) previously reported for the west-central Texas area appear to be anomalous. Perchlorate concentrations were positively correlated with nitrate levels (P < 0.001) but not with chloride concentrations. Opportunities exist for follow-up studies of perchlorate's origins using isotope forensics and for further elucidation of the role of atmospheric processes in the formation or transport of perchlorate.

  4. Bifunctional lanthanum phosphate substrates as novel adsorbents and biocatalyst supports for perchlorate removal

    Energy Technology Data Exchange (ETDEWEB)

    Sankar, Sasidharan [Materials Science and Technology Division (India); Prajeesh, Gangadharan Puthiya Veetil; Anupama, Vijaya Nadaraja [Process Engineering and Environmental Technology Division, CSIR – National Institute for Interdisciplinary Science and Technology, Industrial Estate P.O., Thiruvananthapuram 695019 (India); Krishnakumar, Bhaskaran [Process Engineering and Environmental Technology Division, CSIR – National Institute for Interdisciplinary Science and Technology, Industrial Estate P.O., Thiruvananthapuram 695019 (India); Academy of Scientific and Industrial Research (AcSIR) (India); Hareesh, Padinhattayil [Materials Science and Technology Division (India); Nair, Balagopal N. [R and D Centre, Noritake Co. Ltd., Aichi (Japan); Warrier, Krishna Gopakumar [Materials Science and Technology Division (India); Academy of Scientific and Industrial Research (AcSIR) (India); Hareesh, Unnikrishnan Nair Saraswathy, E-mail: hareesh@niist.res.in [Materials Science and Technology Division (India); Academy of Scientific and Industrial Research (AcSIR) (India)

    2014-06-30

    Graphical abstract: Porous lanthanum phosphate substrates, obtained by an environmentally benign thermal gelation process, performed the role of dual functional sorbent facilitating perchlorate adsorption and bioremediation through the growth of perchlorate reducing microbial colonies. - Highlights: • Lanthanum phosphate monoliths as efficient perchlorate adsorbents. • And also as substrates for biofilm (perchlorate reducing bacteria) growth. • Environmentally benign thermal gelation process for substrate fabrication. • 98% adsorption efficiency for perchlorate concentrations up to 100 μg/L. • The regenerated monoliths show nearly 100% reusability. - Abstract: Porous lanthanum phosphate substrates, obtained by an environmentally benign colloidal forming process employing methyl cellulose, are reported here as excellent adsorbents of perchlorate with >98% efficiency and with 100% reusability. Additionally, the effectiveness of such substrates as biocatalyst supports that facilitate biofilm formation of perchlorate reducing microbes (Serratia marcescens NIIST 5) is also demonstrated for the first time. The adsorption of perchlorate ions is attributed to the pore structure of lanthanum phosphate substrate and the microbial attachment is primarily ascribed to its intrinsic hydrophobic property. Lanthanum phosphate thus emerges as a dual functional material that possesses an integrated adsorption/bioremediation property for the effective removal of ClO{sub 4}{sup −} which is an increasingly important environmental contaminant.

  5. Sympathetic cooling in a rubidium cesium mixture: Production of ultracold cesium atoms

    International Nuclear Information System (INIS)

    This thesis presents experiments for the production of ultracold rubidium cesium mixture in a magnetic trap. The long-termed aim of the experiment is the study of the interaction of few cesium atoms with a Bose-Einstein condensate of rubidium atoms. Especially by controlled variation of the cesium atom number the transition in the description of the interaction by concepts of the one-particle physics to the description by concepts of the many-particle physics shall be studied. The rubidium atoms are trapped in a magneto-optical trap (MOT) and from there reloaded into a magnetic trap. In this the rubidium atoms are stored in the state vertical stroke f=2,mf=2 right angle of the electronic ground state and evaporatively cooled by means of microwave-induced transitions into the state vertical stroke f=1,mf=1] (microwave cooling). The cesium atoms are also trppaed in a MOT and into the same magnetic trap reloaded, in which they are stored in the state vertical stroke f=4,mf=4 right angle of the electronic ground state together with rubidium. Because of the different hyperfine splitting only rubidium is evaporatively cooled, while cesium is cooled jointly sympathetically - i.e. by theramal contact via elastic collisions with rubidium atoms. The first two chapters contain a description of interatomic interactions in ultracold gases as well as a short summary of theoretical concepts in the description of Bose-Einstein condensates. The chapters 3 and 4 contain a short presentation of the methods applied in the experiment for the production of ultracold gases as well as the experimental arrangement; especially in the framework of this thesis a new coil system has been designed, which offers in view of future experiments additionally optical access for an optical trap. Additionally the fourth chapter contains an extensive description of the experimental cycle, which is applied in order to store rubidium and cesium atoms together into the magnetic trap. The last chapter

  6. Intense non-relativistic cesium ion beam

    International Nuclear Information System (INIS)

    The Heavy Ion Fusion group at Lawrence Berkeley Laboratory has constructed the One Ampere Cesium Injector as a proof of principle source to supply an induction linac with a high charge density and high brightness ion beam. This is studied here. An electron beam probe was developed as the major diagnostic tool for characterizing ion beam space charge. Electron beam probe data inversion is accomplished with the EBEAM code and a parametrically adjusted model radial charge distribution. The longitudinal charge distribution was not derived, although it is possible to do so. The radial charge distribution that is derived reveals an unexpected halo of trapped electrons surrounding the ion beam. A charge fluid theory of the effect of finite electron temperature on the focusing of neutralized ion beams (Nucl. Fus. 21, 529 (1981)) is applied to the problem of the Cesium beam final focus at the end of the injector. It is shown that the theory's predictions and assumptions are consistent with the experimental data, and that it accounts for the observed ion beam radius of approx. 5 cm, and the electron halo, including the determination of an electron Debye length of approx. 10 cm

  7. Microbial uptake of uranium, cesium, and radium

    International Nuclear Information System (INIS)

    The ability of diverse microbial species to concentrate uranium, cesium, and radium was examined. Saccharomyces cerevisiae, Pseudomonas aeruginosa, and a mixed culture of denitrifying bacteria accumulated uranium to 10 to 15% of the dry cell weight. Only a fraction of the cells in a given population had visible uranium deposits in electron micrographs. While metabolism was not required for uranium uptake, mechanistic differences in the metal uptake process were indicated. Uranium accumulated slowly (hours) on the surface of S. cerevisiae and was subject to environmental factors (i.e., temperature, pH, interfering cations and anions). In contrast, P. aeruginosa and the mixed culture of denitrifying bacteria accumulated uranium rapidly (minutes) as dense, apparently random, intracellular deposits. This very rapid accumulation has prevented us from determining whether the uptake rate during the transient between the initial and equilibrium distribution of uranium is affected by environmental conditions. However, the final equilibrium distributions are not affected by those conditions which affect uptake by S. cerevisiae. Cesium and radium were concentrated to a considerably lesser extent than uranium by the several microbial species tested. The potential utility of microorganisms for the removal and concentration of these metals from nuclear processing wastes and several bioreactor designs for contacting microorganisms with contaminated waste streams will be discussed

  8. Biosorption behavior and mechanism of cesium-137 on Rhodosporidium fluviale strain UA2 isolated from cesium solution

    International Nuclear Information System (INIS)

    In order to identify a more efficient biosorbent for 137Cs, we have investigated the biosorption behavior and mechanism of 137Cs on Rhodosporidium fluviale (R. fluviale) strain UA2, one of the dominant species of a fungal group isolated from a stable cesium solution. We observed that the biosorption of 137Cs on R. fluviale strain UA2 was a fast and pH-dependent process in the solution composed of R. fluviale strain UA2 (5 g/L) and cesium (1 mg/L). While a Langmuir isotherm equation indicated that the biosorption of 137Cs was a monolayer adsorption, the biosorption behavior implied that R. fluviale strain UA2 adsorbed cesium ions by electrostatic attraction. The TEM analysis revealed that cesium ions were absorbed into the cytoplasm of R. fluviale strain UA2 across the cell membrane, not merely fixed on the cell surface, which implied that a mechanism of metal uptake contributed largely to the cesium biosorption process. Moreover, PIXE and EPBS analyses showed that ion-exchange was another biosorption mechanism for the cell biosorption of 137Cs, in which the decreased potassium ions were replaced by cesium ions. All the above results implied that the biosorption of 137Cs on R. fluviale strain UA2 involved a two-step process. The first step is passive biosorption that cesium ions are adsorbed to cells surface by electrostatic attraction; after that, the second step is active biosorption that cesium ions penetrate the cell membrane and accumulate in the cytoplasm. - Highlights: • Microorganisms isolated from a cesium solution are considered as a biosorbent to remove cesium ions. • The biosorption equilibrium is fitted well to a Langmuir model with a correlation coefficient of 0.9997. • First attempt to explore biosorption mechanisms using PIXE and EPBS. • Living and dead microorganisms have different biosorption mechanisms. • The biosorption of 137Cs involved a two-step process: passive and active

  9. (Dicyanamido)[tris(2-pyridylmethyl)amine]zinc(II) perchlorate

    OpenAIRE

    Shi Guo Zhang; Hong Yan Zhao; Hong Li

    2008-01-01

    In the title complex, [Zn(C2N3)(C18H18N4)]ClO4, the ZnII ion has a slightly distorted trigonal–bipyramidal ZnN5 coordination geometry. The crystal structure is stabilized by weak intermolecular C—H...O and C—H...N hydrogen bonds. In addition, there are relatively close contacts between the O atoms of the perchlorate anion and symmetry-related pyridine rings [O...Cg = 3.179 (3) and 3.236 (3) Å, where Cg is the centroid of a pyridine ring], and between t...

  10. Prediction of Particle Size of Ammonium Perchlorate during Pulverisation

    Directory of Open Access Journals (Sweden)

    Sunil Jain

    2006-07-01

    Full Text Available Ammonium perchlorate has been pulverised by an impact mill (air classifier mill to studythe influence of different operating parameters, viz., effect of mill speed, classifier speed, feedrate, and damper opening (suction rate on the particle size. Further based on the differentgrinding parameters, an empirical equation has been developed and used for the prediction ofparticle size. The experimental results indicate that the values are very close to the predictedones. In addition, particle size distribution has also been studied by applying different modelequations and it has been found that Rosin-Rammler model is the most suitable model for thisoperation.

  11. Comparative DFT study of crystalline ammonium perchlorate and ammonium dinitramide.

    Science.gov (United States)

    Zhu, Weihua; Wei, Tao; Zhu, Wei; Xiao, Heming

    2008-05-22

    The electronic structure, vibrational properties, absorption spectra, and thermodynamic properties of crystalline ammonium perchlorate (AP) and ammonium dinitramide (ADN) have been comparatively studied using density functional theory in the local density approximation. The results shows that the p states for the two solids play a very important role in their chemical reaction. From the low frequency to high frequency region, ADN has more motion modes for the vibrational frequencies than AP. The absorption spectra of AP and ADN display a few, strong bands in the fundamental absorption region. The thermodynamic properties show that ADN is easier to decompose than AP as the temperature increases. PMID:18396853

  12. Specific adsorption of perchlorate anions on Pt{hkl} single crystal electrodes.

    Science.gov (United States)

    Attard, Gary A; Brew, Ashley; Hunter, Katherine; Sharman, Jonathan; Wright, Edward

    2014-07-21

    The voltammetry of Pt{111}, Pt{100}, Pt{110} and Pt{311} single crystal electrodes as a function of perchloric acid concentration (0.05-2.00 M) has been studied in order to test the assertion made in recent reports by Watanabe et al. that perchlorate anions specifically adsorb on polycrystalline platinum. Such an assertion would have significant ramifications for our understanding of electrocatalytic processes at platinum surfaces since perchlorate anions at low pH have classically been assumed not to specifically adsorb. For Pt{111}, it is found that OHad and electrochemical oxide states are both perturbed significantly as perchloric acid concentration is increased. We suggest that this is due to specific adsorption of perchlorate anions competing with OHad for adsorption sites. The hydrogen underpotential deposition (H UPD) region of Pt{111} however remains unchanged although evidence for perchlorate anion decomposition to chloride on Pt{111} is reported. In contrast, for Pt{100} no variation in the onset of electrochemical oxide formation is found nor any shift in the potential of the OHad state which normally results from the action of specifically adsorbing anions. This suggests that perchlorate anions are non-specifically adsorbed on this plane although strong changes in all H UPD states are observed as perchloric acid concentration is increased. This manifests itself as a redistribution of charge from the H UPD state situated at more positive potential to the one at more negative potential. For Pt{110} and Pt{311}, marginal changes in the onset of electrochemical oxide formation are recorded, associated with specific adsorption of perchlorate. Specific adsorption of perchlorate anions on Pt{111} is deleterious to electrocatalytic activity in relation to the oxygen reduction reaction (ORR) as measured using a rotating disc electrode (RDE) in a hanging meniscus configuration. This study supports previous work suggesting that a large component of the ORR

  13. Adsorption of cesium on cement mortar from aqueous solutions.

    Science.gov (United States)

    Volchek, Konstantin; Miah, Muhammed Yusuf; Kuang, Wenxing; DeMaleki, Zack; Tezel, F Handan

    2011-10-30

    The adsorption of cesium on cement mortar from aqueous solutions was studied in series of bench-scale tests. The effects of cesium concentration, temperature and contact time on process kinetics and equilibrium were evaluated. Experiments were carried out in a range of initial cesium concentrations from 0.0103 to 10.88 mg L(-1) and temperatures from 278 to 313 K using coupons of cement mortar immersed in the solutions. Non-radioactive cesium chloride was used as a surrogate of the radioactive (137)Cs. Solution samples were taken after set periods of time and analyzed by inductively coupled plasma mass spectroscopy. Depending on the initial cesium concentration, its equilibrium concentration in solution ranged from 0.0069 to 8.837 mg L(-1) while the respective surface concentration on coupons varied from 0.0395 to 22.34 μg cm(-2). Equilibrium test results correlated well with the Freundlich isotherm model for the entire test duration. Test results revealed that an increase in temperature resulted in an increase in adsorption rate and a decrease in equilibrium cesium surface concentration. Among several kinetic models considered, the pseudo-second order reaction model was found to be the best to describe the kinetic test results in the studied range of concentrations. The adsorption activation energy determined from Arrhenius equation was found to be approximately 55.9 kJ mol(-1) suggesting that chemisorption was the prevalent mechanism of interaction between cesium ions and cement mortar.

  14. Synthesis and peculiarities of the cesium zeolite crystal structure (cesite)

    International Nuclear Information System (INIS)

    An attempt is made to synthesize cesium zeolite by introduction of amorphous seed crystals which correspond by composition with cesium-containing zeolite into the aluminosilicate gel, since this method can produce zeolite with a crystal structure it would not adopt under the usual conditions. It is seen that during crystablization upon introduction of a seed crystal the cesium content in zeolite decreases. A more complete structural elucidation of zeolite obtained by the suggested method was carried out by x0ray and IR spectral analyses. The data of x-ray analysis showed that the structures of synthesized zeolite and binary octagonal pores are similar

  15. Pollution of drug-technical materials by cesium-137

    International Nuclear Information System (INIS)

    Drug-technical raw materials are medicinal plants (flowers, folium, grasses, mushrooms, roots, fruits, berry, kidney, cortex), used in pharmacy. To limit receipt cesium-137 in people body in 1993 in the Republic of Belarus were created 'Temporary permission levels of the cesium-137 radionuclides contents in drug-technical raw materials' were created (TPL-1993). The permission levels of cesium-137 are following: for drug-technical raw material (flowers, folium, grass, mushrooms, roots and other plants parts) - 1850 Bq/kg, for dried up fruits and berries - 2590 Bq/kg. (Author)

  16. Management of cesium loaded AMP- Part I preparation of 137Cesium concentrate and cementation of secondary wastes

    International Nuclear Information System (INIS)

    Separation of 137cesium from High Level Waste can be achieved by use of composite-AMP, an engineered form of Ammonium Molybdo-Phosphate(AMP). Direct vitrification of cesium loaded composite AMP in borosilicate glass matrix leads to separation of water soluble molybdate phase. A proposed process describes two different routes of selective separation of molybdates and phosphate to obtain solutions of cesium concentrates. Elution of 137Cesium from composite-AMP by decomposing it under flow conditions using saturated barium hydroxide was investigated. This method leaves molybdate and phosphate embedded in the column but only 70% of total cesium loaded on column could be eluted. Alternatively composite-AMP was dissolved in sodium hydroxide and precipitation of barium molybdate-phosphate from the resultant solution, using barium nitrate was investigated by batch methods. The precipitation technique gave over 99.9% of 137Cesium activity in solutions, free of molybdates and phosphates, which is ideally suited for immobilization in borosilicate glass matrix. Detailed studies were carried out to immobilize secondary waste of 137Cesium contaminated barium molybdate-phosphate precipitates in the slag cement matrix using vermiculite and bentonite as admixtures. The cumulative fraction of 137Cs leached from the cement matrix blocks was 0.05 in 140 days while the 137Cs leach rate was 0.001 gm/cm2/d. (author)

  17. Structure of double hafnium and cesium sulfate

    International Nuclear Information System (INIS)

    The structure of a compound whose formula according to the structural investigation is Cssub(2+x)Hf(SOsub(4))sub(2+x)(HSOsub(4))sub(2-x)x3Hsub(2)O (x approximately 0.7) (a=10.220, b=12.004, c=15.767 A, space group Pcmn) is determined by diffractometric data (2840 reflections, anisotropic refinement, R=0.087). It is build of complex unions [Hf(SO4)4H2O]4-, Cs+ cations and water molecules. Eight O atoms surrounding Hf atom (dodecahedron Hf-O 2.10-2.22 A) belong to four sulphate groups and water molecule. Three sulphate groups are bidentate-cyclic, and one group - monodentate relative to Hf. The structure has a cesium deficit in particular positions

  18. Biosorption of uranium, radium, and cesium

    International Nuclear Information System (INIS)

    Some fundamental aspects of the biosorption of metals by microbial cells were investigated. These studies were carried out in conjunction with efforts to develop a process to utilize microbial cells as biosorbents for the removal of radionuclides from waste streams generated by the nuclear fuel cycle. It was felt that an understanding of the mechanism(s) of metal uptake would potentially enable the enhancement of the metal uptake phenomenon through environmental or genetic manipulation of the microorganisms. Also presented are the results of a preliminary investigation of the applicability of microorganisms for the removal of 137cesium and 226radium from existing waste solutions. The studies were directed primarily at a characterization of uranium uptake by the yeast, Saccharomyces cerevisiae, and the bacterium, Pseudomonas aeruginosa

  19. Atmospheric transmission for cesium DPAL using TDLAS

    Science.gov (United States)

    Rice, Christopher A.; Perram, Glen P.

    2012-03-01

    The cesium (Cs) Diode Pumped Alkali Laser (DPAL) operates near 894 nm, in the vicinity of atmospheric water vapor absorption lines. An open-path Tunable Diode Laser Absorption (TDLAS) system composed of narrow band (~300 kHz) diode laser fiber coupled to a 12" Ritchey-Chrétien transmit telescope has been used to study the atmospheric transmission characteristics of Cs DPALs over extended paths. The ruggedized system has been field deployed and tested for propagation distances of greater than 1 km. By scanning the diode laser across many free spectral ranges, many rotational absorption features are observed. Absolute laser frequency is monitored with a High Finesse wavemeter to an accuracy of less than 10 MHz. Phase sensitive detection is employed with an absorbance of less than 1% observable under field conditions.

  20. The relationship between perchlorate in drinking water and cord blood thyroid hormones: First experience from Iran

    Directory of Open Access Journals (Sweden)

    Ashraf Javidi

    2015-01-01

    Full Text Available Background: Considering the controversial information regarding the effects of perchlorate on thyroid function of high risk population as neonates, and given the high prevalence rate of thyroid disorders specially congenital hypothyroidism in our region, this study aims to investigate for the first time in Iran, the relationship between drinking groundwater perchlorate and cord blood thyroid hormones level in an industrial region. Methods: In this cross-sectional study, drinking groundwater perchlorate level of rural areas of Zarinshahr, Isfahan was measured. Simultaneously, cord blood level of thyroid hormones of neonates born in the studied region was measured. Thyroid function test of neonates in regions with low and high perchlorate level were compared. Results: In this study, 25 tap water samples were obtained for perchlorate measurement. Level of cord blood thyroid stimulating hormone (TSH, T4 and T3 of 25 neonates were measured. Mean (standard deviation of perchlorate, TSH, T4 and T3 was 3.59 (5.10 μg/l, 7.81 (4.14 mIU/m, 6.06 (0.85 mg/dl, and 63.46 (17.53 mg/dl, respectively. Mean levels of thyroid function tests were not different in low ( 0.05. Conclusions: Perchlorate did not appear to be related to thyroid function of neonates in the studied industrial region. It seems that iodine status of the regions, as well as other environmental contaminants and genetic background, could impact on its relation with thyroid function of neonates.

  1. Sorption of cesium and strontium by arid region desert soil

    International Nuclear Information System (INIS)

    Adsorption and ion exchange in soil systems are the principal mechanisms that retard the migration of nuclear waste to the biosphere. Cesium and strontium are two elements with radioactive isotopes (Cs137 and Sr90) that are commonly disposed of as nuclear waste. The sorption and ion exchange properties of nonradioactive cesium and strontium were studied in this investigation. The soil used in this study was collected at an experimental infiltration site on Frenchman Flat, a closed drainage basin on the Nevada Test Site. This soil is mostly nonsaline-alkali sandy loam and loamy sand with a cation exchange capacity ranging from 13 to 30 me/100g. The clay fraction of the soil contains illite, montmorillonite, and clinoptilolite. Ion exchange studies have shown that this soil sorbs cesium preferentially relative to strontium, and that charge for charge, the exchange-phase cations released from exchange sites exceed the cesium and strontium sorbed by the soil. 38 references, 22 figures

  2. Perchlorate Exposure Reduces Primordial Germ Cell Number in Female Threespine Stickleback.

    Science.gov (United States)

    Petersen, Ann M; Earp, Nathanial C; Redmond, Mandy E; Postlethwait, John H; von Hippel, Frank A; Buck, C Loren; Cresko, William A

    2016-01-01

    Perchlorate is a common aquatic contaminant that has long been known to affect thyroid function in vertebrates, including humans. More recently perchlorate has been shown to affect primordial sexual differentiation in the aquatic model fishes zebrafish and threespine stickleback, but the mechanism has been unclear. Stickleback exposed to perchlorate from fertilization have increased androgen levels in the embryo and disrupted reproductive morphologies as adults, suggesting that perchlorate could disrupt the earliest stages of primordial sexual differentiation when primordial germ cells (PGCs) begin to form the gonad. Female stickleback have three to four times the number of PGCs as males during the first weeks of development. We hypothesized that perchlorate exposure affects primordial sexual differentiation by reducing the number of germ cells in the gonad during an important window of stickleback sex determination at 14-18 days post fertilization (dpf). We tested this hypothesis by quantifying the number of PGCs at 16 dpf in control and 100 mg/L perchlorate-treated male and female stickleback. Perchlorate exposure from the time of fertilization resulted in significantly reduced PGC number only in genotypic females, suggesting that the masculinizing effects of perchlorate observed in adult stickleback may result from early changes to the number of PGCs at a time critical for sex determination. To our knowledge, this is the first evidence of a connection between an endocrine disruptor and reduction in PGC number prior to the first meiosis during sex determination. These findings suggest that a mode of action of perchlorate on adult reproductive phenotypes in vertebrates, including humans, such as altered fecundity and sex reversal or intersex gonads, may stem from early changes to germ cell development. PMID:27383240

  3. Perchlorate Exposure Reduces Primordial Germ Cell Number in Female Threespine Stickleback

    Science.gov (United States)

    Petersen, Ann M.; Earp, Nathanial C.; Redmond, Mandy E.; Postlethwait, John H.; von Hippel, Frank A.; Buck, C. Loren; Cresko, William A.

    2016-01-01

    Perchlorate is a common aquatic contaminant that has long been known to affect thyroid function in vertebrates, including humans. More recently perchlorate has been shown to affect primordial sexual differentiation in the aquatic model fishes zebrafish and threespine stickleback, but the mechanism has been unclear. Stickleback exposed to perchlorate from fertilization have increased androgen levels in the embryo and disrupted reproductive morphologies as adults, suggesting that perchlorate could disrupt the earliest stages of primordial sexual differentiation when primordial germ cells (PGCs) begin to form the gonad. Female stickleback have three to four times the number of PGCs as males during the first weeks of development. We hypothesized that perchlorate exposure affects primordial sexual differentiation by reducing the number of germ cells in the gonad during an important window of stickleback sex determination at 14–18 days post fertilization (dpf). We tested this hypothesis by quantifying the number of PGCs at 16 dpf in control and 100 mg/L perchlorate-treated male and female stickleback. Perchlorate exposure from the time of fertilization resulted in significantly reduced PGC number only in genotypic females, suggesting that the masculinizing effects of perchlorate observed in adult stickleback may result from early changes to the number of PGCs at a time critical for sex determination. To our knowledge, this is the first evidence of a connection between an endocrine disruptor and reduction in PGC number prior to the first meiosis during sex determination. These findings suggest that a mode of action of perchlorate on adult reproductive phenotypes in vertebrates, including humans, such as altered fecundity and sex reversal or intersex gonads, may stem from early changes to germ cell development. PMID:27383240

  4. Perchlorate Exposure Reduces Primordial Germ Cell Number in Female Threespine Stickleback.

    Directory of Open Access Journals (Sweden)

    Ann M Petersen

    Full Text Available Perchlorate is a common aquatic contaminant that has long been known to affect thyroid function in vertebrates, including humans. More recently perchlorate has been shown to affect primordial sexual differentiation in the aquatic model fishes zebrafish and threespine stickleback, but the mechanism has been unclear. Stickleback exposed to perchlorate from fertilization have increased androgen levels in the embryo and disrupted reproductive morphologies as adults, suggesting that perchlorate could disrupt the earliest stages of primordial sexual differentiation when primordial germ cells (PGCs begin to form the gonad. Female stickleback have three to four times the number of PGCs as males during the first weeks of development. We hypothesized that perchlorate exposure affects primordial sexual differentiation by reducing the number of germ cells in the gonad during an important window of stickleback sex determination at 14-18 days post fertilization (dpf. We tested this hypothesis by quantifying the number of PGCs at 16 dpf in control and 100 mg/L perchlorate-treated male and female stickleback. Perchlorate exposure from the time of fertilization resulted in significantly reduced PGC number only in genotypic females, suggesting that the masculinizing effects of perchlorate observed in adult stickleback may result from early changes to the number of PGCs at a time critical for sex determination. To our knowledge, this is the first evidence of a connection between an endocrine disruptor and reduction in PGC number prior to the first meiosis during sex determination. These findings suggest that a mode of action of perchlorate on adult reproductive phenotypes in vertebrates, including humans, such as altered fecundity and sex reversal or intersex gonads, may stem from early changes to germ cell development.

  5. Sorption of cesium on Olkiluoto mica gneiss, granodiorite and granite

    Energy Technology Data Exchange (ETDEWEB)

    Huitti, T.; Hakanen, M. [Univ. of Helsinki (Finland). Lab. of Radiochemistry; Lindberg, A. [Geological Survey of Finland, Espoo (Finland)

    1998-09-01

    Cesium was selected as a model to study the sorption in bedrock occurring by ion exchange mechanism. The aim of the study was to supplement the existing data on sorption occurring by ion exchange mechanism in bedrock of the candidate sites for spent fuel disposal at Olkiluoto. The sorption of cesium was studied on crushed mica gneiss, tonalite (granodiorite) and granite in artificial groundwaters. Fresh water was represented by Allard water, pH 8 and pH 7, and saline water by Ol-So water, pH 7 and pH 9. In addition, a Na-Ca-Cl brine water and its 1:10 dilution were used as simulants. Cesium concentrations were between 10{sup -8} and 10{sup -3} mol/l. The distribution coefficients of the sorption, R{sub d} and R{sub a} values were determined by batch method. Isotherms were partly non-linear with slopes 0.7 - 1.0 depending on rock and water. At the end of the sorption experiment, the water was analysed for cations exchanged for cesium. The sorption of cesium was also studied as a function of ionic strength. The ionic strength increased in the order Allard < 0l-Br 1:10 < 0l-So < 0l-Br. The sorption of cesium was lower at higher ionic strength and higher Cs concentration. The mineral composition of rocks was determined by thin section analysis, and the sorption distribution ratios on thin sections in the different waters were determined by batch technique. The minerals, that sorbed most cesium were determined by autoradiography. These were biotite, muscovite and chlorite. Cordierite in mica gneiss also sorbed cesium very effectively. (orig.) 12 refs.

  6. Adsorption Behaviour of Liquid 4He on Cesium Substrates

    OpenAIRE

    Iov, Valentin

    2004-01-01

    The aim of this thesis is to investigate the wetting properties of 4He on cesium substrates using optical and electrical methods. Due to the fact that the cesium substrates are deposited at low temperatures onto a thin silver underlayer, it is necessary firstly to study and understand the adsorption of helium on silver. The work presented here is structured as follows: some of the fundamental concepts on the theory of physisorbed films, such as van der Waals interaction, adsorption isotherms ...

  7. Detoxification of PAX-21 ammunitions wastewater by zero-valent iron for microbial reduction of perchlorate

    International Nuclear Information System (INIS)

    Highlights: → Ammonium perchlorate, hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX) and 2,4-dinitroanisole (DNAN) are the major constituents of PAX-21. → DNAN is identified as the primary toxicant responsible for inhibiting the activity of perchlorate reducing bacteria. → Iron treatment not only removes energetic compounds but also eliminates the toxic constituents that inhibit the subsequent microbial process. - Abstract: US Army and the Department of Defense (DoD) facilities generate perchlorate (ClO4-) from munitions manufacturing and demilitarization processes. Ammonium perchlorate is one of the main constituents in Army's new main charge melt-pour energetic, PAX-21. In addition to ammonium perchlorate, hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX) and 2,4-dinitroanisole (DNAN) are the major constituents of PAX-21. In order to evaluate microbial perchlorate reduction as a practical option for the treatment of perchlorate in PAX-21 wastewater, we conducted biodegradation experiments using glucose as the primary sources of electrons and carbon. Batch experiments showed that negligible perchlorate was removed in microbial reactors containing PAX-21 wastewater while control bottles containing seed bacteria and glucose rapidly and completely removed perchlorate. These results suggested that the constituents in PAX-21 wastewater may be toxic to perchlorate reducing bacteria. A series of batch toxicity test was conducted to identify the toxic constituents in PAX-21 and DNAN was identified as the primary toxicant responsible for inhibiting the activity of perchlorate reducing bacteria. It was hypothesized that pretreatment of PAX-21 by zero-valent iron granules will transform toxic constituents in PAX-21 wastewater to non-toxic products. We observed complete reduction of DNAN to 2,4-diaminoanisole (DAAN) and RDX to formaldehyde in abiotic iron reduction study. After a 3-day acclimation period, perchlorate in iron-treated PAX-21 wastewater was rapidly decreased to

  8. Seasonal variation of cesium 134 and cesium 137 in semidomestic reindeer in Norway after the Chernobyl accident

    Directory of Open Access Journals (Sweden)

    I.M. H. Eikelmann

    1990-09-01

    Full Text Available The Chernobyl accident had a great impact on the semidomestic reindeer husbandry in central Norway. Seasonal differences in habitat and diet resulted in large variations in observed radiocesium concentrations in reindeer after the Chernobyl accident. In three areas with high values of cesium-134 and cesium-137 in lichens, the main feed for reindeer in winter, reindeer were sampled every second month to monitor the seasonal variation and the decrease rate of the radioactivity. The results are based on measurements of cesium-134 and cesium-137 content in meat and blood and by whole-body monitoring of live animals. In 1987 the increase of radiocesium content in reindeer in Vågå were 4x from August to January. The mean reductions in radiocesium content from the winter 1986/87 to the winter 1987/88 were 32%, 50% and 43% in the areas of Vågå, Østre-Namdal and Lom respectively.

  9. Dissimilatory reduction of perchlorate and other common pollutants by a consortium enriched from tidal flats of the Yellow Sea

    Institute of Scientific and Technical Information of China (English)

    Nirmala Bardiya; Jae-Ho Bae

    2015-01-01

    Objective: To enrich a facultative anaerobic bacterial consortium from the Yellow Sea and assess its ability to reduce perchlorate and other co-pollutants. Methods: Bacterial consortium collected from the tidal flats of the Yellow Sea was enriched in an anoxic medium containing perchlorate as the electron (e-) acceptor and acetate as the electron (e-) donor. The enriched consortium was then tested for perchlorate reduction under different perchlorate concentrations and in the presence of nitrate by using standard anaerobic techniques. The complete enzymatic reduction of perchlorate to chloride was confirmed by chlorite dismutation. Ability of the consortium to grow with alternate e- acceptors was also tested with acetate as the e- donor. Results: The enriched consortium could rapidly reduce perchlorate up to the initial concentration of 25.65 mmol/L. In the presence of nitrate, perchlorate reduction did not occur immediately and reduction of nitrate started after a lag phase, with concomitant accumulation of nitrite. The perchlorate-enriched consortium could reduce chlorate, oxygen, Cr (VI), and selenate as the alternate e- acceptors but failed to utilize sulfate, thiosulfate, sulfite, and nitrite. Conclusions: The consortium from the tidal flats of the Yellow Sea could reduce perchlorate and co-contaminants such as chlorate, nitrate, Cr (VI), and selenate under heterotrophic conditions with acetate as the e- donor and carbon source. While perchlorate was completely dismutated into innocuous chloride and oxygen, accumulation of nitrite occurred during the reduction of nitrate.

  10. Perchlorate: Health Effects and Technologies for Its Removal from Water Resources

    Directory of Open Access Journals (Sweden)

    Thiruvenkatachari Viraraghavan

    2009-04-01

    Full Text Available Perchlorate has been found in drinking water and surface waters in the United States and Canada. It is primarily associated with release from defense and military operations. Natural sources include certain fertilizers and potash ores. Although it is a strong oxidant, perchlorate is very persistent in the environment. At high concentrations perchlorate can affect the thyroid gland by inhibiting the uptake of iodine. A maximum contaminant level has not been set, while a guidance value of 6 ppb has been suggested by Health Canada. Perchlorate is measured in environmental samples primarily by ion chromatography. It can be removed from water by anion exchange or membrane filtration. Biological and chemical processes are also effective in removing this species from water.

  11. The Impact of Temperature on the Performance of Anaerobic Biological Treatment of Perchlorate in Drinking Water

    Science.gov (United States)

    A 20 month pilot-scale study was conducted to examine the impact of temperature on the performance of an anaerobic biological contactor used to treat perchlorate-contaminated water. The contactor was successfully acclimated with indigenous microorganisms. Influent temperatures ...

  12. ANALYSIS OF HYDROPONIC FERTILIZER MATRIXES FOR PERCHLORATE: COMPARISON OF ANALYTICAL TECHNIQUES

    Science.gov (United States)

    Seven retail hydroponic nitrate fertilizer products, two liquid and five solid, were comparatively analyzed for the perchlorate anion (ClO4-) by ion chromatography (IC) with suppressed conductivity detection, complexation electrospray ionization mass spectrometry (cESI-MS), norma...

  13. A rapid and simple method for the separation of TBP-dodecane by perchloric acid

    International Nuclear Information System (INIS)

    Organic solvents, including TBP etc., are widely used as an extractant, and treated and disposed by storage, incineration, and absorption into absorbent after they were used. Any of those methods does not aim at recycling of solvents, treating concurrently the extractant and the diluent without separating them. In this paper, a test is reported on the TBP-dodecane separation by perchloric acid for a separation test of the diluent from the extractant as a first step toward recycling. Basically this separation method is already reported by P. Mark et al. as a method for the analysis of TBP, but it requires a large amount of perchloric acid. With a further detailed study of the perchloric acid effects on the TBP-dodecane separation, it was made clear that the separation is possible by adding a fixed amount of TBP contacted with perchloric acid to the TBP-dodecane solvent. In this paper, its outline is presented. (author)

  14. Preparation of perlite-based magnesium perchlorate desiccant with colour indicator.

    Science.gov (United States)

    Wu, L; He, H

    1994-05-01

    A new desiccant consisting of magnesium perchlorate, expanded perlite and metal chelate was prepared. The performance tests show that the desiccant is superior to magnesium perchlorate desiccant in dehydration efficiency, absorption capacity for water, flow resistance, color indicator and regeneration. It can reduce the amount of water in gases to approximately 0.7 ppm(v/v). Its applications in gas analysis and purification were investigated.

  15. Perchlorate in dust fall and indoor dust in Malta: An effect of fireworks.

    Science.gov (United States)

    Vella, Alfred J; Chircop, Cynthia; Micallef, Tamara; Pace, Colette

    2015-07-15

    We report on the presence of perchlorate in the settleable dust of Malta, a small central Mediterranean island. Both dust fall collected directly as it precipitated from atmosphere over a period of one month and deposited indoor dust from domestic residences were studied. Perchlorate was determined by ion chromatography of water extracts of the collected dusts. Dust fall was collected from 43 towns during 2011 to 2013 and indoor dust was sampled from homes in the same localities. Perchlorate was detected in 108 of 153 samples of dust fall (71%) and in 28 of 37 indoor dust samples (76%). Detectable perchlorate in dust fall ranged from 0.52μgg(-1) to 561μgg(-1) with a median value of 6.2μgg(-1); in indoor dust, levels were from 0.79μgg(-1) to 53μgg(-1) with a median value of 7.8μgg(-1), the highest recorded anywhere to date. Statistical analysis suggested that there was no significant difference in perchlorate content of indoor dust and dust fall. Perchlorate levels in dust fall escalate during the summer in response to numerous religious feasts celebrated with fireworks and perchlorate persists at low μgg(-1) concentrations for several months beyond the summer festive period. In Malta, perchlorate derives exclusively from KClO4, imported for fireworks manufacture. Its residue in dust presents an exposure risk to the population, especially via ingestion by hand to mouth transfer. Our results suggest that wherever intensive burning of fireworks takes place, the environmental impact may be much longer lived than realised, mainly due to re-suspension and deposition of contaminated settled dust in the urban environment. PMID:25828411

  16. Perchlorate in dust fall and indoor dust in Malta: An effect of fireworks.

    Science.gov (United States)

    Vella, Alfred J; Chircop, Cynthia; Micallef, Tamara; Pace, Colette

    2015-07-15

    We report on the presence of perchlorate in the settleable dust of Malta, a small central Mediterranean island. Both dust fall collected directly as it precipitated from atmosphere over a period of one month and deposited indoor dust from domestic residences were studied. Perchlorate was determined by ion chromatography of water extracts of the collected dusts. Dust fall was collected from 43 towns during 2011 to 2013 and indoor dust was sampled from homes in the same localities. Perchlorate was detected in 108 of 153 samples of dust fall (71%) and in 28 of 37 indoor dust samples (76%). Detectable perchlorate in dust fall ranged from 0.52μgg(-1) to 561μgg(-1) with a median value of 6.2μgg(-1); in indoor dust, levels were from 0.79μgg(-1) to 53μgg(-1) with a median value of 7.8μgg(-1), the highest recorded anywhere to date. Statistical analysis suggested that there was no significant difference in perchlorate content of indoor dust and dust fall. Perchlorate levels in dust fall escalate during the summer in response to numerous religious feasts celebrated with fireworks and perchlorate persists at low μgg(-1) concentrations for several months beyond the summer festive period. In Malta, perchlorate derives exclusively from KClO4, imported for fireworks manufacture. Its residue in dust presents an exposure risk to the population, especially via ingestion by hand to mouth transfer. Our results suggest that wherever intensive burning of fireworks takes place, the environmental impact may be much longer lived than realised, mainly due to re-suspension and deposition of contaminated settled dust in the urban environment.

  17. Cesium and strontium in Black Sea macroalgae

    International Nuclear Information System (INIS)

    The trace level of metals and particularly radioactive ones should be monitored to evaluate the transfer along the trophic chain, assess the risk for biota and can be used for global changes assessment. Plants respond rapidly to all changes in the ecosystem conditions and are widely used as indicators and predictors for changes in hydrology and geology. In this work we represent our successful development and applications of a methodology for monitoring of stable and radioactive strontium and cesium in marine biota (Black Sea algae's). In case of radioactive release they are of high interest. We use ED-XRF, gamma spectrometers and LSC instrumentation and only 0.25 g sample. Obtained results are compared with those of other authors in same regions. The novelty is the connection between the radioactive isotopes and their stable elements in algae in time and space scale. All our samples were collected from Bulgarian Black Sea coast. - Highlights: • An extraction chromatography method for radiochemical separation of Sr and Cs. • Assessment of Sr and Cs accumulation capacity of six Black Sea macroalgae species. • Connection between the isotopes and their stable elements content in algae. • Assessment of Sr and Cs content in ecosystems along the Bulgarian coast

  18. A screened hybrid density functional study on energetic complexes: Cobalt, nickel and copper carbohydrazide perchlorates

    International Nuclear Information System (INIS)

    Graphical abstract: The molecular geometry, electronic structure, infrared spectra, and heats of reaction and formation of cobalt and nickel tris(carbohydrazide) perchlorates as well as copper bis(carbohydrazide) perchlorate are investigated using the HSE screened hybrid density functional. The metal-ligand interaction, thermal stability, and red-shift of the amino stretching vibrations of these complexes are also discussed. Moreover, it is found there is a relationship between the energy gap and impact sensitivity. - Abstract: The molecular geometry, electronic structure, infrared spectra and thermochemical properties of cobalt and nickel tris(carbohydrazide) perchlorates (CoCP and NiCP) as well as copper bis(carbohydrazide) perchlorate (CuCP) were investigated using the Heyd-Scuseria-Ernzerhof (HSE) screened hybrid density functional. The results show that both perchlorate ions coordinate with the copper atom, and the interactions between copper and perchlorate are ionic, whereas all the metal-carbohydrazide interactions are covalent. Due to the delocalization from the σN-H bond orbital to the n*M antibond orbital, the amino stretching vibrations of these complexes show considerable red-shift compared with those of free carbohydrazide ligand. The calculated heats of reaction and formation indicate that the formations of these complexes are exothermic, and the order of their thermal stability is NiCP > CoCP > CuCP. These agree well with the experimental results. Finally, we find that there is a relationship between the energy gap and impact sensitivity.

  19. Microbial redox processes in deep subsurface environments and the potential application of (perchlorate in oil reservoirs

    Directory of Open Access Journals (Sweden)

    Martin G Liebensteiner

    2014-09-01

    Full Text Available The ability of microorganisms to thrive under oxygen-free conditions in subsurface environments relies on the enzymatic reduction of oxidized elements, such as sulfate, ferric iron or CO2, coupled to the oxidation of inorganic or organic compounds. A broad phylogenetic and functional diversity of microorganisms from subsurface environments has been described using isolation-based and advanced molecular ecological techniques. The physiological groups reviewed here comprise iron-, manganese- and nitrate-reducing microorganisms. In the context of recent findings also the potential of chlorate and perchlorate [jointly termed (perchlorate] reduction in oil reservoirs will be discussed. Special attention is given to elevated temperatures that are predominant in the deep subsurface. Microbial reduction of (perchlorate is a thermodynamically favorable redox process, also at high temperature. However, knowledge about (perchlorate reduction at elevated temperatures is still scarce and restricted to members of the Firmicutes and the archaeon Archaeoglobus fulgidus. By analyzing the diversity and phylogenetic distribution of functional genes in (metagenome databases and combining this knowledge with extrapolations to earlier-made physiological observations we speculate on the potential of (perchlorate reduction in the subsurface and more precisely oil fields. In addition, the application of (perchlorate for bioremediation, souring control and microbial enhanced oil recovery are addressed.

  20. Impacts of natural organic matter on perchlorate removal by an advanced reduction process.

    Science.gov (United States)

    Duan, Yuhang; Batchelor, Bill

    2014-01-01

    Perchlorate can be destroyed by Advanced Reduction Processes (ARPs) that combine chemical reductants (e.g., sulfite) with activating methods (e.g., UV light) in order to produce highly reactive reducing free radicals that are capable of rapid and effective perchlorate reduction. However, natural organic matter (NOM) exists widely in the environment and has the potential to influence perchlorate reduction by ARPs that use UV light as the activating method. Batch experiments were conducted to obtain data on the impacts of NOM and wavelength of light on destruction of perchlorate by the ARPs that use sulfite activated by UV light produced by low-pressure mercury lamps (UV-L) or by KrCl excimer lamps (UV-KrCl). The results indicate that NOM strongly inhibits perchlorate removal by both ARP, because it competes with sulfite for UV light. Even though the absorbance of sulfite is much higher at 222 nm than that at 254 nm, the results indicate that a smaller amount of perchlorate was removed with the UV-KrCl lamp (222 nm) than with the UV-L lamp (254 nm). The results of this study will help to develop the proper way to apply the ARPs as practical water treatment processes. PMID:24521418

  1. Preliminary analyses for perchlorate in selected natural materials and their derivative products

    Science.gov (United States)

    Orris, G.J.; Harvey, G.J.; Tsui, D.T.; Eldrige, J.E.

    2003-01-01

    Increasing concern about sources of perchlorate contamination in ground and surface waters has led to interest in identifying potential sources of natural perchlorate and products derived from these natural sources. To date, most perchlorate found in ground and surface waters has been attributed to its major uses as an oxidizer in solid propellants for rockets, in fireworks and other explosives, and a variety of other uses of man-made perchlorate salts. However, perchlorate found in the soils, surface water, and ground water of some locations cannot be linked to an anthropogenic source. This paper contains preliminary data on the detection and non-detection of perchlorate in a variety of natural materials and their products, including some fertilizer materials. These data were previously presented at two conferences; once in poster session and once orally (Harvey and others, 1999; Orris and others, 2000). Although the results presented here are included in a journal article awaiting publication, the lack of public information on this topic has led to repeated requests for the data used as the basis for our presentations in 1999 and 2000.

  2. Perchlorate reduction by hydrogen autotrophic bacteria and microbial community analysis using high-throughput sequencing.

    Science.gov (United States)

    Wan, Dongjin; Liu, Yongde; Niu, Zhenhua; Xiao, Shuhu; Li, Daorong

    2016-02-01

    Hydrogen autotrophic reduction of perchlorate have advantages of high removal efficiency and harmless to drinking water. But so far the reported information about the microbial community structure was comparatively limited, changes in the biodiversity and the dominant bacteria during acclimation process required detailed study. In this study, perchlorate-reducing hydrogen autotrophic bacteria were acclimated by hydrogen aeration from activated sludge. For the first time, high-throughput sequencing was applied to analyze changes in biodiversity and the dominant bacteria during acclimation process. The Michaelis-Menten model described the perchlorate reduction kinetics well. Model parameters q(max) and K(s) were 2.521-3.245 (mg ClO4(-)/gVSS h) and 5.44-8.23 (mg/l), respectively. Microbial perchlorate reduction occurred across at pH range 5.0-11.0; removal was highest at pH 9.0. The enriched mixed bacteria could use perchlorate, nitrate and sulfate as electron accepter, and the sequence of preference was: NO3(-) > ClO4(-) > SO4(2-). Compared to the feed culture, biodiversity decreased greatly during acclimation process, the microbial community structure gradually stabilized after 9 acclimation cycles. The Thauera genus related to Rhodocyclales was the dominated perchlorate reducing bacteria (PRB) in the mixed culture.

  3. Viscosity and crystallization mechanism of cesium loaded iron phosphate glasses

    Energy Technology Data Exchange (ETDEWEB)

    Joseph, Kitheri, E-mail: joskit@igcar.gov.in [Chemistry Group, IGCAR, Kalpakkam 603 102 (India); Kutty, K.V. Govindan [Chemistry Group, IGCAR, Kalpakkam 603 102 (India); Goswami, M.C. [National Metallurgical Laboratory, Jamshedpur 831 007 (India); Rao, P.R. Vasudeva [Chemistry Group, IGCAR, Kalpakkam 603 102 (India)

    2014-07-01

    Highlights: • Melt viscosity of cesium loaded iron phosphate glasses is measured and reported for the first time. • Viscosity – temperature followed Arrhenius model. • Activation energy of viscous flow is strongly correlated to glass transition temperature of the glasses. • Process of crystallization of cesium loaded glass by approximation-free kinetic method to understand the mechanism. • Cesium loaded IPG and IPG shows bulk crystallization mechanism. - Abstract: This paper describes the melt viscosity behaviour and the crystallization mechanism of a series of iron phosphate glasses. High temperature viscosity measurements were carried out on pristine iron phosphate glass and a series of cesium loaded iron phosphate glasses in order to understand the effect of addition of Cs{sub 2}O on viscosity of iron phosphate glasses. Activation energy of viscous flow was estimated from the experimental data by applying Arrhenius model of viscosity–temperature relationship. Activation energy of viscous flow is observed to be strongly correlated to glass transition temperature of these glasses. Fragility of iron phosphate and cesium loaded iron phosphate glass systems were also evaluated in region of high temperature. Crystallization of these glasses was studied using thermal analysis techniques. Temperature integral approximation free method was utilized to evaluate the kinetic parameters such as activation energy of crystallization (E{sub c}) and Avrami exponent (n). The value of Avrami exponent ‘n’ obtained showed that the glasses under present study crystallize via bulk crystallization mechanism, i.e., nucleation and three dimensional growth.

  4. Cesium corrosion process in Fe–Cr steel

    International Nuclear Information System (INIS)

    A cesium corrosion out-pile test was performed to Fe–Cr steel in a simulated fuel pin environment. In order to specify the corrosion products, the corroded area was analyzed by scanning electron microscopy (SEM) and transmission electron microscopy (TEM). A cesium corrosion process in Fe–Cr steel was successfully developed proceeding from both experimental results and thermochemical consideration. The corroded area was mainly formed by Fe layer and Fe depleted oxidized layer. The Fe depleted oxidized layer was formed by Cr0.5Fe0.5 and Cr2O3. The presumed main corrosion reactions were 2Cr+2/3 O2→Cr2O3(ΔG650°C=-894.1kJ/mol) and Cr23C6+46Cs+46O2→23Cs2CrO4+6C(ΔG650°C=-25018.1kJ/mol). Factors of these reactions are chromium, carbon, oxygen and cesium. Therefore, cesium corrosion progression must be dependent on the chromium content, carbon content in the steel, the supply rate of oxygen and temperature which correlated with the diffusion rate of cesium and oxygen into the specimen

  5. Viscosity and crystallization mechanism of cesium loaded iron phosphate glasses

    International Nuclear Information System (INIS)

    Highlights: • Melt viscosity of cesium loaded iron phosphate glasses is measured and reported for the first time. • Viscosity – temperature followed Arrhenius model. • Activation energy of viscous flow is strongly correlated to glass transition temperature of the glasses. • Process of crystallization of cesium loaded glass by approximation-free kinetic method to understand the mechanism. • Cesium loaded IPG and IPG shows bulk crystallization mechanism. - Abstract: This paper describes the melt viscosity behaviour and the crystallization mechanism of a series of iron phosphate glasses. High temperature viscosity measurements were carried out on pristine iron phosphate glass and a series of cesium loaded iron phosphate glasses in order to understand the effect of addition of Cs2O on viscosity of iron phosphate glasses. Activation energy of viscous flow was estimated from the experimental data by applying Arrhenius model of viscosity–temperature relationship. Activation energy of viscous flow is observed to be strongly correlated to glass transition temperature of these glasses. Fragility of iron phosphate and cesium loaded iron phosphate glass systems were also evaluated in region of high temperature. Crystallization of these glasses was studied using thermal analysis techniques. Temperature integral approximation free method was utilized to evaluate the kinetic parameters such as activation energy of crystallization (Ec) and Avrami exponent (n). The value of Avrami exponent ‘n’ obtained showed that the glasses under present study crystallize via bulk crystallization mechanism, i.e., nucleation and three dimensional growth

  6. The diffusion of cesium, strontium, and europium in silicon carbide

    Science.gov (United States)

    Dwaraknath, S. S.; Was, G. S.

    2016-08-01

    A novel multi-layer diffusion couple was used to isolate the diffusion of strontium, europium and cesium in SiC without introducing radiation damage to SiC and at concentrations below the solubility limit for the fission products in SiC. Diffusion occurred by both bulk and grain boundary pathways for all three fission products between 900∘ C and 1 ,300∘ C. Cesium was the fastest diffuser below 1 ,100∘ C and the slowest above this temperature. Strontium and europium diffusion tracked very closely as a function of temperature for both bulk and grain boundary diffusion. Migration energies ranged from 1.0 eV to 5.7 eV for bulk diffusion and between 2.2 eV and 4.7 eV for grain boundary diffusion. These constitute the first measurements of diffusion of cesium, europium, and strontium in silicon carbide, and the magnitude of the cesium diffusion coefficient supports the premise that high quality TRISO fuel should have minimal cesium release.

  7. Inhibition of microbial sulfate reduction in a flow-through column system by (per)chlorate treatment

    OpenAIRE

    Anna eEngelbrektson; Christopher eHubbard; Lauren eTom; Aaron eBOUSSINA; Yong Tae eJin; Hayden eWong; Yvette Marisa Piceno; Hans Karl Carlson; Mark eConrad; Andersen, Gary L.; Coates, John D.

    2014-01-01

    Microbial sulfate reduction is a primary cause of oil reservoir souring. Here we show that amendment with chlorate or perchlorate [collectively (per)chlorate] potentially resolves this issue. Triplicate packed columns inoculated with marine sediment were flushed with coastal water amended with yeast extract and one of nitrate, chlorate, or perchlorate. Results showed that although sulfide production was dramatically reduced by all treatments, effluent sulfide was observed in the nitrate (10 m...

  8. Dissociative excitation of cesium atom upon e-CsOH collisions

    International Nuclear Information System (INIS)

    The process of dissociative excitation of cesium atom in collisions with mono-kinetic molecules of cesium hydroxide is studied. It is established that behaviour of dissociative excitations the cesium atom in spectral series corresponds of to the grade dependence of cross sections on the main quantum number of the upper level. The values of constants, characterizing the behaviour of cross sections in the eight spectral series of the cesium atom are determined

  9. Study of microbial perchlorate reduction: Considering of multiple pH, electron acceptors and donors

    Energy Technology Data Exchange (ETDEWEB)

    Xu, Xing [Key Laboratory of Water Pollution Control and Recycling (Shandong), School of Environmental Science and Engineering, Shandong University, Jinan 250100 (China); Gao, Baoyu, E-mail: bygao@sdu.edu.cn [Key Laboratory of Water Pollution Control and Recycling (Shandong), School of Environmental Science and Engineering, Shandong University, Jinan 250100 (China); Jin, Bo [School of Chemical Engineering, The University of Adelaide, Adelaide SA 5005,Australia (Australia); Zhen, Hu [Key Laboratory of Water Pollution Control and Recycling (Shandong), School of Environmental Science and Engineering, Shandong University, Jinan 250100 (China); Wang, Xiaoyi [CSIRO Land and Water, Gate 5, Waite Road, Urrbrae, SA 5064 (Australia); Dai, Ming [School of Chemical Engineering, The University of Adelaide, Adelaide SA 5005,Australia (Australia)

    2015-03-21

    Graphical abstract: Schemes of perchlorate reduction in ClO{sub 4}{sup −}/ClO{sub 3}{sup −}–NO{sub 3}{sup −} e{sup −}acceptor systems. - Highlights: • We created a multiple electron acceptor/donor system for ClO{sub 4}{sup −} reduction. • Nitrate reduction was inhibited when using perchlorate-grown Azospira sp. KJ. • Reduction proceeded as an order of ClO{sub 3}{sup −}, ClO{sub 4}{sup −}and NO{sub 3}{sup −}. • Oxidation of acetate was inhibited by succinate in acetate–succinate series. - Abstract: Bioremediation of perchlorate-cotaminated water by a heterotrophic perchlorate reducing bacterium creates a multiple electron acceptor-donor system. We experimentally determined the perchlorate reduction by Azospira sp. KJ at multiple pH, electron acceptors and donors systems; this was the aim of this study. Perchlorate reduction was drastically inhibited at the pH 6.0, and the maximum reduction of perchlorate by Azospira sp. KJ was observed at pH value of 8.0. Perchlorate reduction was retarded in ClO{sub 4}{sup −}–ClO{sub 3}{sup −}, ClO{sub 4}{sup −}–ClO{sub 3}{sup −}–NO{sub 3}{sup −},and ClO{sub 4}{sup −}–NO{sub 3}{sup −} acceptor systems, while being completely inhibited by the additional O{sub 2} in the ClO{sub 4}{sup −}–O{sub 2} acceptor system. The reduction proceeded as an order of ClO{sub 3}{sup −}, ClO{sub 4}{sup −}, and NO{sub 3}{sup −} in the ClO{sub 4}{sup −}–ClO{sub 3}{sup −}–NO{sub 3}{sup −} system. K{sub S,}v{sub max}, and q{sub max} obtained at different e{sup −} acceptor and donor conditions are calculated as 140.5–190.6 mg/L, 8.7–13.2 mg-perchlorate/L-h, and 0.094–0.16 mg-perchlorate/mg-DW-h, respectively.

  10. Study of microbial perchlorate reduction: Considering of multiple pH, electron acceptors and donors

    International Nuclear Information System (INIS)

    Graphical abstract: Schemes of perchlorate reduction in ClO4−/ClO3−–NO3− e−acceptor systems. - Highlights: • We created a multiple electron acceptor/donor system for ClO4− reduction. • Nitrate reduction was inhibited when using perchlorate-grown Azospira sp. KJ. • Reduction proceeded as an order of ClO3−, ClO4−and NO3−. • Oxidation of acetate was inhibited by succinate in acetate–succinate series. - Abstract: Bioremediation of perchlorate-cotaminated water by a heterotrophic perchlorate reducing bacterium creates a multiple electron acceptor-donor system. We experimentally determined the perchlorate reduction by Azospira sp. KJ at multiple pH, electron acceptors and donors systems; this was the aim of this study. Perchlorate reduction was drastically inhibited at the pH 6.0, and the maximum reduction of perchlorate by Azospira sp. KJ was observed at pH value of 8.0. Perchlorate reduction was retarded in ClO4−–ClO3−, ClO4−–ClO3−–NO3−,and ClO4−–NO3− acceptor systems, while being completely inhibited by the additional O2 in the ClO4−–O2 acceptor system. The reduction proceeded as an order of ClO3−, ClO4−, and NO3− in the ClO4−–ClO3−–NO3− system. KS,vmax, and qmax obtained at different e− acceptor and donor conditions are calculated as 140.5–190.6 mg/L, 8.7–13.2 mg-perchlorate/L-h, and 0.094–0.16 mg-perchlorate/mg-DW-h, respectively

  11. Possible Detection of Perchlorates by the Sample Analysis at Mars (SAM) Instrument: Comparison with Previous Missions

    Science.gov (United States)

    Navarro-Gonzalex, Rafael; Sutter, Brad; Archer, Doug; Ming, Doug; Eigenbrode, Jennifer; Franz, Heather; Glavin, Daniel; McAdam, Amy; Stern, Jennifer; McKay, Christopher; Coll, Patrice; Cabane, Michel; Mahaffy, Paul; Conrad, Pamela; Martin-Torres, Francisco; Zorzano-Mier, Maria; Grotzinger, John

    2013-01-01

    The first chemical analysis of soluble salts in the soil was carried out by the Phoenix Lander in the Martian Arctic [1]. Surprisingly, chlorine was present as magnesium or calcium perchlorate at 0.4 to 0.6 percent. Additional support for the identification of perchlorate came from the evolved gas analysis which detected the release of molecular oxygen at 350-550C [1]. When Mars-like soils from the Atacama Desert were spiked with magnesium perchlorate (1 percent) and heated using the Viking GC-MS protocol, nearly all the organics were combusted but a small amount was chlorinated, forming chloromethane and dichloromethane [2]. These chlorohydrocarbons were detected by the Viking GC-MS experiments when the Martian soil was analyzed but they were considered to be terrestrial contaminants [3]. Reinterpretation of the Viking results suggests <0.1 percent perchlorate and ppm levels of organic carbon at landing site 1 and 2 [2]. The suggestion of perchlorate in the Viking sites [2] has been challenged on the grounds that the detected compounds (CH3Cl and CH2Cl2) were carried from Earth [4]. Recently the Sample Analysis at Mars (SAM) instrument on board the Mars Science Laboratory (MSL) ran four samples from an aeolian bedform named Rocknest. The samples analyzed were portioned from the fifth scoop at this location. The samples were heated to 835C at 35C/min with a He flow. The SAM QMS detected a major oxygen release (300-500C) [5], coupled with the release of chlorinated hydrocarbons (chloromethane, dichloromethane, trichloromethane, and chloromethylpropene) detected both by SAM QMS and GC-MS derived from known Earth organic contaminants in the instrument [6]. Calcium perchlorate appears to be the best candidate for evolved O2 in the Rocknest samples at this time but other Cl species (e.g., chlorates) are possible and must be evaluated. The potential detection of perchlorates in Rocknest material adds weight to the argument that both Viking Landers measured signatures of

  12. Particle size distribution and perchlorate levels in settled dust from urban roads, parks, and roofs in Chengdu, China.

    Science.gov (United States)

    Li, Yiwen; Shen, Yang; Pi, Lu; Hu, Wenli; Chen, Mengqin; Luo, Yan; Li, Zhi; Su, Shijun; Ding, Sanglan; Gan, Zhiwei

    2016-01-01

    A total of 27 settled dust samples were collected from urban roads, parks, and roofs in Chengdu, China to investigate particle size distribution and perchlorate levels in different size fractions. Briefly, fine particle size fractions (intake is safe to both children and adults in Chengdu, China. However, due to perchlorate mainly existing in fine particles, there is a potential for perchlorate to transfer into surface water and the atmosphere by runoff and wind erosion or traffic emission, and this could act as an important perchlorate pollution source for the indoor environment, and merits further study. PMID:26608047

  13. Cesium in the Savannah River Site environment

    Energy Technology Data Exchange (ETDEWEB)

    Carlton, W.H.; Bauer, L.R.; Evans, A.G.; Geary, L.A.; Murphy, C.E. Jr.; Pinder, J.E.; Strom, R.N.

    1992-03-01

    Cesium in the Savannah River Site Environment is published as a part of the Radiological Assessment Program (RAP). It is the fourth in a series of eight documents on individual radioisotopes released to the environment as a result of Savannah River Site (SRS) operations. The earlier documents describe the environmental consequences of tritium, iodine, and uranium. Documents on plutonium, strontium, carbon, and technetium will be published in the future. These are dynamic documents and current plans call for revising and updating each one on a two-year schedule.Radiocesium exists in the environment as a result of above-ground nuclear weapons tests, the Chernobyl accident, the destruction of satellite Cosmos 954, small releases from reactors and reprocessing plants, and the operation of industrial, medical, and educational facilities. Radiocesium has been produced at SRS during the operation of five production reactors. Several hundred curies of [sup 137]Cs was released into streams in the late 50s and 60s from leaking fuel elements. Smaller quantities were released from the fuel reprocessing operations. About 1400 Ci of [sup 137]Cs was released to seepage basins where it was tightly bound by clay in the soil. A much smaller quantity, about four Ci. was released to the atmosphere. Radiocesium concentration and mechanisms for atmospheric, surface water, and groundwater have been extensively studied by Savannah River Technology Center (SRTC) and ecological mechanisms have been studied by Savannah River Ecology Laboratory (SREL). The overall radiological impact of SRS releases on the offsite maximum individual can be characterized by total doses of 033 mrem (atmospheric) and 60 mrem (liquid), compared with a dose of 12,960 mrem from non-SRS sources during the same period of time. Isotope [sup 137]Cs releases have resulted in a negligible risk to the environment and the population it supports.

  14. Cesium in the Savannah River Site environment

    Energy Technology Data Exchange (ETDEWEB)

    Carlton, W.H.; Bauer, L.R.; Evans, A.G.; Geary, L.A.; Murphy, C.E. Jr.; Pinder, J.E.; Strom, R.N.

    1992-03-01

    Cesium in the Savannah River Site Environment is published as a part of the Radiological Assessment Program (RAP). It is the fourth in a series of eight documents on individual radioisotopes released to the environment as a result of Savannah River Site (SRS) operations. The earlier documents describe the environmental consequences of tritium, iodine, and uranium. Documents on plutonium, strontium, carbon, and technetium will be published in the future. These are dynamic documents and current plans call for revising and updating each one on a two-year schedule.Radiocesium exists in the environment as a result of above-ground nuclear weapons tests, the Chernobyl accident, the destruction of satellite Cosmos 954, small releases from reactors and reprocessing plants, and the operation of industrial, medical, and educational facilities. Radiocesium has been produced at SRS during the operation of five production reactors. Several hundred curies of {sup 137}Cs was released into streams in the late 50s and 60s from leaking fuel elements. Smaller quantities were released from the fuel reprocessing operations. About 1400 Ci of {sup 137}Cs was released to seepage basins where it was tightly bound by clay in the soil. A much smaller quantity, about four Ci. was released to the atmosphere. Radiocesium concentration and mechanisms for atmospheric, surface water, and groundwater have been extensively studied by Savannah River Technology Center (SRTC) and ecological mechanisms have been studied by Savannah River Ecology Laboratory (SREL). The overall radiological impact of SRS releases on the offsite maximum individual can be characterized by total doses of 033 mrem (atmospheric) and 60 mrem (liquid), compared with a dose of 12,960 mrem from non-SRS sources during the same period of time. Isotope {sup 137}Cs releases have resulted in a negligible risk to the environment and the population it supports.

  15. Controllable evaporation of cesium from a dispenser oven

    Science.gov (United States)

    Fantz, U.; Friedl, R.; Fröschle, M.

    2012-12-01

    This instrument allows controlled evaporation of the alkali metal cesium over a wide range of evaporation rates. The oven has three unique features. The first is an alkali metal reservoir that uses a dispenser as a cesium source. The heating current of the dispenser controls the evaporation rate allowing generation of an adjustable and stable flow of pure cesium. The second is a blocking valve, which is fully metallic as is the body of the oven. This construction both reduces contamination of the dispenser and enables the oven to be operated up to 300 °C, with only small temperature variations (metal at a cold spot is significantly hindered. The last feature is an integral surface ionization detector for measuring and controlling the evaporation rate. The dispenser oven can be easily transferred to the other alkali-metals.

  16. Dating of mine waste in lacustrine sediments using cesium-137

    Science.gov (United States)

    Rember, W. C.; Erdman, T. W.; Hoffmann, M. L.; Chamberlain, V. E.; Sprenke, K. F.

    1993-11-01

    For over a century Medicine Lake in northern Idaho has received heavy-metal-laden tailings from the Coeur d'Alene mining district. Establishing the depositional chronology of the lake bottom sediments provides information on the source and rate of deposition of the tailings. Cesium-137, an isotope produced in the atmosphere by nuclear bomb tests, was virtually absent in the environment prior to 1951, but reached its apex in 1964. Our analysis of cesium-137 in the sediments of Medicine Lake revealed that 14 cm of fine-grained tailings were deposited in the lake from 1951 to 1964 and tailing deposition downstream was greatly reduced by the installation of tailings dams in the district in 1968. Cesium-137 analysis is accomplished by a fairly simple gamma-ray counting technique and should be a valuable tool for analyzing sedimentation in any lacustrine environment that was active during the 1950s and 1960s.

  17. Cesium 137 in oils and plants from Guatemala

    International Nuclear Information System (INIS)

    Since 1990 the project of radioactive and environmental contamination started in Guatemala. Studies about the radioactive contamination levels are made within the framework of this project. Cesium-137 has been an interest radionuclide, because it is a fission product released to the environment by the use of nuclear weapons and nuclear power plants accidents. The sampling consisted in collection of soil and grass in 20 provinces of Guatemala, one point by province, and it was made in 1990. The cesium-137 concentration in the samples, was determined by gamma spectrometry, using an hyper pure germanium detector. The results show the presence of radioactive contamination in soil and grass due to cesium-137, at levels that might be considered as normal. The levels found are not harmful for human health, and its importance is the fact that can be used as reference levels for the environmental radioactivity monitoring in Guatemala

  18. Study of radiatively sustained cesium plasmas for solar energy conversion

    Science.gov (United States)

    Palmer, A. J.; Dunning, G. J.

    1980-01-01

    The results of a study aimed at developing a high temperature solar electric converter are reported. The converter concept is based on the use of an alkali plasma to serve as both an efficient high temperature collector of solar radiation as well as the working fluid for a high temperature working cycle. The working cycle is a simple magnetohydrodynamic (MHD) Rankine cycle employing a solid electrode Faraday MHD channel. Research milestones include the construction of a theoretical model for coupling sunlight in a cesium plasma and the experimental demonstration of cesium plasma heating with a solar simulator in excellent agreement with the theory. Analysis of a solar MHD working cycle in which excimer laser power rather than electric power is extracted is also presented. The analysis predicts a positive gain coefficient on the cesium-xenon excimer laser transition.

  19. Inhibition of microbial sulfate reduction in a flow-through column system by (perchlorate treatment

    Directory of Open Access Journals (Sweden)

    Anna eEngelbrektson

    2014-06-01

    Full Text Available Microbial sulfate reduction is a primary cause of oil reservoir souring. Here we show that amendment with chlorate or perchlorate [collectively (perchlorate] potentially resolves this issue. Triplicate packed columns inoculated with marine sediment were flushed with coastal water amended with yeast extract and one of nitrate, chlorate, or perchlorate. Results showed that although sulfide production was dramatically reduced by all treatments, effluent sulfide was observed in the nitrate (10 mM treatment after an initial inhibition period. In contrast, no effluent sulfide was observed with (perchlorate (10 mM. Microbial community analyses indicated temporal community shifts and phylogenetic clustering by treatment. Nitrate addition stimulated Xanthomonadaceae and Rhizobiaceae growth, supporting their role in nitrate metabolism. (Perchlorate showed distinct effects on microbial community structure compared with nitrate and resulted in a general suppression of the community relative to the untreated control combined with a significant decrease in sulfate reducing species abundance indicating specific toxicity. Furthermore, chlorate stimulated Pseudomonadaceae and Pseudoalteromonadaceae, members of which are known chlorate respirers, suggesting that chlorate may also control sulfidogenesis by biocompetitive exclusion of sulfate-reduction. Perchlorate addition stimulated Desulfobulbaceae and Desulfomonadaceae, which contain sulfide oxidizing and elemental sulfur-reducing species respectively, suggesting that effluent sulfide concentrations may be controlled through sulfur redox cycling in addition to toxicity and biocompetitive exclusion. Sulfur isotope analyses further support sulfur cycling in the columns, even when sulfide is not detected. This study indicates that (perchlorate show great promise as inhibitors of sulfidogenesis in natural communities and provides insight into which organisms and respiratory processes are involved.

  20. Hydrogen oxidation on gold electrode in perchloric acid solution

    Energy Technology Data Exchange (ETDEWEB)

    Sustersic, M.G.; Almeida, N.V.; Von Mengershausen, A.E. [Facultad de Ingenieria y Ciencias Economico Sociales, Universidad Nacional de San Luis, 25 de Mayo N 384, 5730 Villa Mercedes, San Luis (Argentina)

    2010-06-15

    The aim of this research is to study the interface gold/perchloric acid solution in presence of hydrogen. The reactive is generated by H{sup +} ion reduction and by saturating the electrolyte with the gaseous H{sub 2}. No evidence of H{sub 2} dissociative adsorption is found. In special conditions, a strongly adsorbed layer is formed from the atoms diffusing from inside of the metal. The mass transport occurs in three ways: the diffusion of H atoms inwards, the diffusion of H atoms back to the surface and the dissolved H{sub 2} diffusion from the bulk electrolyte to the surface. When dissolved H{sub 2} reacts, the reaction is kinetically controlled when the H{sub 2} partial pressure is high, and it is diffusionally controlled when the reactive partial pressure is low. Above 0.7 V, (measured vs. RHE), the (100) plane surface reconstruction lifts, and the rate determining step is the H diffusion towards inside of the metal, and the current suddenly falls. The Hydrogen redox reaction on gold shows reversibility with respect to the potential when the reactives are the H diffusing outwards of the metal and the H{sup +} ion present in the electrolyte. However, the absolute current values of oxidation and reduction are different because the reactive sources are different. (author)

  1. Chlorine-36 abundance in natural and synthetic perchlorate

    Energy Technology Data Exchange (ETDEWEB)

    Heikoop, Jeffrey M [Los Alamos National Laboratory; Dale, M [NON LANL; Sturchio, Neil C [UNIV OF ILLIONOIS; Caffee, M [PURDUE UNIV; Belosa, A D [UNIV OF ILLINOIS; Heraty, Jr., L J [UNIV OF ILLINOIS; Bohike, J K [RESTON, VA; Hatzinger, P B [SHAW ENIVIORNMENTAL C0.; Jackson, W A [TEXAS TECH; Gu, B [ORNL

    2009-01-01

    Perchlorate (ClO{sub 4}{sup -}) is ubiquitous in the environment. It occurs naturally as a product of atmospheric photochemical reactions, and is synthesized for military, aerospace, and industrial applications. Nitrate-enriched soils of the Atacama Desert (Chile) contain high concentrations of natural ClO{sub 4}{sup -}; nitrate produced from these soils has been exported worldwide since the mid-1800's for use in agriculture. The widespread introduction of synthetic and agricultural ClO{sub 4}{sup -} into the environment has complicated attempts to understand the geochemical cycle of ClO{sub 4}{sup -}. Natural ClO{sub 4}{sup -} samples from the southwestern United States have relatively high {sup 36}Cl abundances ({sup 36}Cl/Cl = 3,100 x 10{sup -15} to 28,800 x 10{sup -15}), compared with samples of synthetic ({sup 36}Cl/Cl = 0.0 x 10{sup -15} to 40 x 10{sup -15}) and Atacama Desert ({sup 36}Cl/Cl = 0.9 x 10{sup -15} to 590 x 10{sup -15}) ClO{sub 4}{sup -}. These data give a lower limit for the initial {sup 36}Cl abundance of natural ClO{sub 4}{sup -} and provide temporal and other constraints on its geochemical cycle.

  2. Kinetics of chlorite dismutase in a perchlorate degrading reactor sludge.

    Science.gov (United States)

    Nadaraja, Anupama Vijaya; Veetil, Prajeesh Gangadharan Puthiya; Vidyadharan, Athira; Bhaskaran, Krishnakumar

    2013-01-01

    Kinetics of chlorite dismutase (CD), the terminal enzyme involved in the perchlorate (ClO4(-)) reduction pathway, in a ClO4(-)-degrading bioreactor are reported in this study. Enzyme activity was determined from dissolved oxygen released during disproportionation of chlorite (ClO2(-)). CD activity was in the range 29.8-36.4 U/mg dry weight sludge, and kinetic constants Vmax and K(m) of the enzyme were 37.83 U/mg dry weight and 0.28 mM, respectively. Among reactor operational conditions, enzyme activity was observed at pH 4.0-9.0, with an optimum at pH 6.0. Redox potential in the range -50 to +120mV and NaCl up to 3.5 g/L had no significant effect on CD activity. However, co-occurring pollutants such as ammonium at 10 ppm, nitrite at 50 ppm and EDTA at 100 microM reduced CD activity substantially. The present study highlights ideal bioreactor conditions to avoid ClO2(-) toxicity, while indicating the buffering potential of a mixed microbial system against inhibiting factors to maintain stable CD activity in bioreactors.

  3. NOVEL ASSOCIATIONS BETWEEN URINARY PERCHLORATE AND POTENTIALLY RELEVANT EFFECTS ON RISK FACTORS FOR HEART DISEASE BASED ON NHANES 2001-2002

    Science.gov (United States)

    Perchlorate is a widespread environmental pollutant, and is a thyroid hormone disruptor. A previous population study based on the National Health and Nutrition Examination Survey (NHANES) 2001-2002 database showed that urinary perchlorate concentrations were associated with signi...

  4. Adaptive evolution of Desulfovibrio alaskensis G20 for developing resistance to perchlorate

    Science.gov (United States)

    Mehta-Kolte, M. G.; Youngblut, M.; Redford, S.; Gregoire, P.; Carlson, H. K.; Coates, J. D.

    2015-12-01

    Due to its toxic, explosive, and corrosive nature, inadvertent biological H2S production by sulfate reducing microorganisms (SRM) poses significant health and industrial operational risks. Anthropogenic sources are dominated by the oil industry where H2S in reservoir gases and fluids has an associated annual cost estimated at $90 billion globally. Our previous studies have identified perchlorate (ClO4-) as a selective and potent inhibitor of SRM in pure culture and complex microbial ecosystems. However, constant addition of inhibitors like perchlorate to natural ecosystems may result in a new adaptive selective pressure on SRM populations. With this in mind we investigated the ability of Desulfovibrio alaskensis G20, a model oil reservoir SRM, to adapt to perchlorate and develop a resistance. Serial transfers of three parallel cultures with increasing concentrations of perchlorate up to 100 mM were generated and compared to wild-type strains that were transferred for same number of generations in absence of perchlorate. Genome sequencing revealed that all three adapted strains had single non-synonymous single-nucleotide polymorphisms in the same gene, Dde_2265, the sulfate adenylytransferase (ATP sulfurylase (ATPS)) (EC 2.7.7.4). ATPS catalyzes the first committed step in sulfate reduction and is essential in all SRM. IC50s against growth for these evolved strains demonstrated a three-fold increased resistance to perchlorate compared to wild-type controls. These evolved strains also had 5x higher transcriptional abundance of Dde_2265 compared to the wild-type strain. Biochemical characterization of the purified ATPS enzyme from both wild-type and the evolved strain showed that the mutant ATPS from the evolved strain was resistant to perchlorate inhibition of ATP turnover with a KI for perchlorate that was 3x greater relative to the wild-type ATPS. These results demonstrate that a single-base pair mutation in ATPS can have a significant impact on developing

  5. Highly Selective Perchlorate Membrane Electrode Based on Cobalt(Ⅲ) Schiff Base as a Neutral Carrier

    Institute of Scientific and Technical Information of China (English)

    SHOKROLLAHI Ardeshir; GHAEDI Mehrorang; RAJABI, Harold Reza; KIANFAR, Ali Hossein

    2009-01-01

    A highly selective poly(vinyl chloride) (PVC) membrane electrode based on Co(Ⅲ)-Schiff base [Co(5-NO2-Salen)(PBu3)]ClO4·H2O (where 5-NO2-SalenH=bis(5-nitrosalycilaldehyde)ethylenediamine) as a new carrier for construction of perchlorate-selective electrode by incorporating the membrane ingredients on the surface of a graphite electrodes has been reported. The proposed electrode possesses a very wide Nernestian potential linear range to perchlorate from 1.0×10-6 to 5.0×10-1 mol·L-1 with a slope of (59.4±0.9) mV per decade of perchlo-rate concentration with a low detection limit of 5.0×10-7 mol·L-1 and good perchlorate selectivity over the wide variety of other anions. The developed electrode has an especially fast response (<5 s) and a wide pH independent range (3.0-12.0) in comparison with recent reported electrodes and can be used for at least 2 months without any considerable divergence in their potential response. This electrode was used for the determination of perchlorate in river water, drinking water, sludgy water and human urine with satisfactory results without complicated and time consuming pretreatment.

  6. Developmental timing of sodium perchlorate exposure alters angiogenesis, thyroid follicle proliferation and sexual maturation in stickleback.

    Science.gov (United States)

    Furin, Christoff G; von Hippel, Frank A; Postlethwait, John H; Buck, C Loren; Cresko, William A; O'Hara, Todd M

    2015-08-01

    Perchlorate, a common aquatic contaminant, is well known to disrupt homeostasis of the hypothalamus-pituitary-thyroid axis. This study utilizes the threespine stickleback (Gasterosteus aculeatus) fish to determine if perchlorate exposure during certain windows of development has morphological effects on thyroid and gonads. Fish were moved from untreated water to perchlorate-contaminated water (30 and 100mg/L) starting at 0, 3, 7, 14, 21, 42, 154 and 305 days post fertilization until approximately one year old. A reciprocal treatment (fish in contaminated water switched to untreated water) was conducted on the same schedule. Perchlorate exposure increased angiogenesis and follicle proliferation in thyroid tissue, delayed gonadal maturity, and skewed sex ratios toward males; effects depended on concentration and timing of exposure. This study demonstrates that perchlorate exposure beginning during the first 42 days of development has profound effects on stickleback reproductive and thyroid tissues, and by implication can impact population dynamics. Long-term exposure studies that assess contaminant effects at various stages of development provide novel information to characterize risk to aquatic organisms, to facilitate management of resources, and to determine sensitive developmental windows for further study of underlying mechanisms. PMID:25865142

  7. Perchlorate and Nitrate Remediation Efficiency and Microbial Diversity in a Containerized Wetland Bioreactor

    Energy Technology Data Exchange (ETDEWEB)

    Jr., B D; Dibley, V; Pinkart, H; Legler, T

    2004-06-09

    We have developed a method to remove perchlorate (14 to 27 {micro}g/L) and nitrate (48 mg/L) from contaminated groundwater using a wetland bioreactor. The bioreactor has operated continuously in a remote field location for more than two years with a stable ecosystem of indigenous organisms. This study assesses the bioreactor for long-term perchlorate and nitrate remediation by evaluating influent and effluent groundwater for reduction-oxidation conditions and nitrate and perchlorate concentrations. Total community DNA was extracted and purified from 10-g sediment samples retrieved from vertical coring of the bioreactor during winter. Analysis by denaturing gradient gel electrophoresis of short, 16S rDNA, polymerase-chain-reaction products was used to identify dominant microorganisms. Bacteria genera identified were closely affiliated with bacteria widely distributed in soils, mud layers, and fresh water. Of the 17 dominant bands sequenced, most were gram negative and capable of aerobic or anaerobic respiration with nitrate as the terminal electron acceptor (Pseudomonas, Acinetobacter, Halomonas, and Nitrospira). Several identified genera (Rhizobium, Acinetobactor, and Xanthomonas) are capable of fixing atmospheric nitrogen into a combined form (ammonia) usable by host plants. Isolates were identified from the Proteobacteria class, known for the ability to reduce perchlorate. Initial bacterial assessments of sediments confirm the prevalence of facultative anaerobic bacteria capable of reducing perchlorate and nitrate in situ.

  8. [Determination of iodide, thiocyanate and perchlorate ions in environmental water by two-dimensional ion chromatography].

    Science.gov (United States)

    Lin, Li; Wang, Haibo; Shi, Yali

    2013-03-01

    A procedure for the determination of iodide, thiocyanate and perchlorate ions in environmental water by two-dimensional ion chromatography has been developed. At first the iodide, thiocyanate and perchlorate ions were separated from interfering ions by a column (IonPac AS16, 250 mm x 4 mm). The iodide ion, thiocyanate and perchlorate ions were then enriched with an enrichment column (MAC-200, 80 mm x 0.75 mm). In the 2nd-dimensional chromatography, iodide thiocyanate and perchlorate ions were separated and quantified by a capillary column (IonPac AS20 Capillary, 250 mm x 0.4 mm). The linear ranges were 0.05 -100 pg/L with correlation coefficients of 0. 999 9, and the detection limits were 0. 02 - 0.05 micro gg/L. The spiked recoveries of iodide, thiocyanate and perchlorate ions were in the range of 85.1% to 100.1%. The relative standard deviations of the recoveries were 1.7% to 4.9%.

  9. Effectiveness of removal of aqueous perchlorate by Cuprilig, a copper(II) derivative of Octolig.

    Science.gov (United States)

    Martin, Dean F; Kondis, Nicholas P; Alldredge, Robert L

    2009-02-01

    The present study describes the effectiveness of removal of perchlorate ion by Octolig a commercially available immobilized ligand, IMLIG, and by Cuprilig, the cupric ion derivative of this material. Octolig consists of polyethylenediamine moieties covalently bound to a high-surface area silica gel (CAS Registry number = 404899-06-5). Perchlorate in drinking water is a nuisance anion that escapes from firms that produce rocket fuel, batteries, and fireworks and becomes a contaminant of groundwater. It may also be a natural component of the environment. Perchlorate ion can interfere with thyroid function and may also cause birth defects. Perchlorate contamination of water supplies is serious because of the difficulty in removing it, especially in the western United States where a combination of drought and water shortages exacerbate the problems of supplying safe drinking water to an increasing population. In this study, aqueous solutions were passed over a chromatography column containing samples of Cuprilig. Test water contained 70 microg perchlorate/L and effluent was below detection level (water and in well water. Analyses were performed by a commercial laboratory. Mechanisms of interaction are proposed. PMID:19123099

  10. Effects of lanthanum nitrate on growth and chlorophyll fluorescence characteristics of Alternanthera philoxeroides under perchlorate stress

    Institute of Scientific and Technical Information of China (English)

    谢寅峰; 蔡贤雷; 刘伟龙; 陶功胜; 陈倩; 张强

    2013-01-01

    To investigate the effects of exogenous lanthanum (La) on Alternanthera philoxeroides (Mart.) Griseb under perchlorate stress, changes in the growth and physiological parameters were investigated in solution culture experiments under controlled condi-tions. Different concentrations of La (NO3)3 were used in our study. It was shown that 0.1 and 0.5 mg/L La3+alleviated the inhibition effect of perchlorate on A. philoxeroides, including relative growth yield, dry weight of different organs, leaf area and root activity. And La3+prevented decline in the relative chlorophyll content and chlorophyll fluorescence parameters including Fv/Fm, Fv'/Fm',ΦPSI and ETR induced by perchlorate stress. Moreover, 0.5 mg/L La3+showed an optimal mitigative effect, while excess La3+(5.0 mg/L) led to synergistic effect on stress. Correlation analysis revealed a significant positive relationship between growth indexes and the chlorophyll fluorescence parameters, root activity and relative chlorophyll content (p<0.05). The results suggested that appropriate concentration of La3+could effectively alleviate growth inhibition and injury of A. philoxeroides caused by perchlorate stress, and the mitigative effect of La3+might be achieved by improving root activity, maintaining chlorophyll content and promoting photochemical efficiency of photosystem II of A. philoxeroides under perchlorate stress.

  11. Sorption of cesium in young till soils

    Energy Technology Data Exchange (ETDEWEB)

    Lusa, Merja; Lempinen, Janne; Ahola, Hanna; Soederlund, Mervi; Lehto, Jukka [Helsinki Univ. (Finland). Laboratory of Radiochemistry; Lahdenperae, Anne-Maj [Saanio and Riekkola Oy, Consulting Engineers, Helsinki (Finland); Ikonen, Ari T.K. [Posiva Oy, Eurajoki (Finland)

    2014-10-01

    Soil samples from three forest soil pits were examined down to a depth of approximately three metres using 1 M ammonium acetate extraction and microwave-assisted extraction with concentrated nitric acid (HNO{sub 3}), to study the binding of cesium (Cs) at Olkiluoto Island, southern Finland. Ammonium acetate was used to extract the readily exchangeable Cs fractions roughly representing the Cs fraction in soil which is available for plants. Microwave-assisted HNO{sub 3} extraction dissolves various minerals, e.g. carbonates, most sulphides, arsenides, selenides, phosphates, molybdates, sulphates, iron (Fe) and manganese (Mn) oxides and some silicates (olivine, biotite, zeolite), and reflects the total Cs concentrations. Cs was mostly found in the strongly bound fraction obtained through HNO{sub 3} extraction. The average Cs concentrations found in this fraction were 3.53 ± 0.30 mg/kg (d.w.), 3.06 ± 1.86 mg/kg (d.w.) and 1.83 ± 0.42 mg/kg (d.w.) in the three soil pits, respectively. The average exchangeable Cs found in the ammonium acetate extraction in all three sampling pits was 0.015 ± 0.008 mg/kg (d.w.). In addition, Cs concentrations in the soil solution were determined and in situ distribution coefficients (K{sub d}) for Cs were calculated. Furthermore, the in situ K{sub d} data was compared with the Cs K{sub d} data obtained using the model batch experiments. The in situ K{sub d} values were observed to fairly well follow the trend of batch sorption data with respect to soil depth, but on average the batch distribution coefficients were almost an order of magnitude higher than the in situ K{sub d} data. In situ Cs sorption data could be satisfactory fitted with the Langmuir sorption isotherm, but the Freundlich isotherm failed to fit the data. Finally, distribution coefficients were calculated by an ion exchange approach using soil solution data, the cation exchange capacity (CEC) as well as Cs to sodium (Na) and Cs to potassium (K) ion exchange selectivity

  12. Cesium-137 Levels Detected in Otters from Austria

    Directory of Open Access Journals (Sweden)

    Gutleb A.C.

    1991-02-01

    Full Text Available Pollution seems to be one of the most important causes for the decline of the European otter (Lutra lutra. The accident in the Chernobyl nuclear power plant added another aspect to environmental pollution. Few data on cesium-137 contents in otters are available, so levels were measured in 3 otters from Austria. All levels found were very low.

  13. Membrane-based separation technologies for cesium, strontium, and technetium

    Energy Technology Data Exchange (ETDEWEB)

    Kafka, T.

    1996-10-01

    This work is one of two parallel projects that are part of an ESP task to develop high-capacity, selective, solid extractants for cesium, strontium, and technetium from nuclear wastes. In this subtask, Pacific Northwest National Laboratory (PNNL) is collaborating with 3M, St. Paul, Minnesota, working in cooperation with IBC Advanced Technologies, American Fork, Utah.

  14. Cesium Ion Exchange Using Tank 241-AN-104 Supernate

    International Nuclear Information System (INIS)

    The River Protection Project is to design and build a high level nuclear waste treatment facility. The waste treatment plant is to process millions of gallons of radioactive waste stored in tanks at the Hanford Site. The high level nuclear waste treatment process includes various unit operations, such as ultrafiltration, precipitation, evaporation, ion exchange, and vitrification. Ion exchange is identified as the optimal treatment method for removal of cesium-137 and Tc-99 from the waste. Extensive ion exchange testing was performed using small-scale columns with actual waste samples. The objectives of this study were to: demonstrate SuperLig 644 ion exchange performance and process steps for the removal of cesium from actual AN-104 tank waste; pretreat actual AN-104 tank waste to reduce the concentration of cesium-137 in the waste below LAW vitrification limit; produce and characterize cesium eluate solutions for use in eluate evaporation tests. The experiments consisted of batch contact and small-scale column tests. The batch contact tests measured sorption partition coefficients Kds. The Kds were used to predict the effective resin capacity. The small-scale column tests, which closely mimic plant conditions, generated loading and elution profile data used to determine whether removal targets and design requirements were met

  15. Discovery of Cesium, Lanthanum, Praseodymium and Promethium Isotopes

    OpenAIRE

    May, E.; Thoennessen, M

    2011-01-01

    Currently, forty-one cesium, thirty-five lanthanum, thirty-two praseodymium, and thirty-one promethium, isotopes have been observed and the discovery of these isotopes is discussed here. For each isotope a brief synopsis of the first refereed publication, including the production and identification method, is presented.

  16. Strontium-90 and cesium-137 in fresh water

    International Nuclear Information System (INIS)

    Japan Chemical Analysis Center has analysed the strontium-90 and Cesium-137 contents in fresh water from 7 prefectures in Japan by the commission of Science and Technology Agency of Japanese Government. The method described in ''Radioactivity Survey Data in Japan No. 43 (NIRS-RSD-43, 1977) was applied to the analysis of these two radionuclides in samples. (author)

  17. Kinetics of nitrate and perchlorate reduction in ion exchange brine using the membrane biofilm reactor (MBfR)

    Science.gov (United States)

    Several sources of bacterial inocula were tested for their ability to reduce nitrate and perchlorate in synthetic ion-exchange spent brine (3-4.5% salinity) using a hydrogen-based membrane biofilm reactor (MBfR). Nitrate and perchlorate removal fluxes reached as high as 5.4 g N ...

  18. Martian Chlorine Chemistry: A Study of Perchlorate on the Martian Surface, Evidence of an Ongoing Formation Mechanism and Implications of a Complex Chlorine Cycle

    Science.gov (United States)

    Carrier, Brandi L.

    2015-10-01

    The research presented herein addresses the detection of perchlorate on Mars, evidence of perchlorate in Mars meteorite EETA 79001, determination of the perchlorate parent salts at the Phoenix landing site, and the ongoing formation of perchlorate from chloride minerals as well as from other oxychlorine species. The detection of perchlorate in three samples by the Phoenix Wet Chemistry Laboratory and the implication of these results are discussed. The further detection of perchlorate in Mars meteorite EETA 79001 by ion chromatography and the determination of the parent salts of the perchlorate detected at the Phoenix landing site by electrochemical analyses and ion chromatography are detailed and the implications of the identity of the parent salts are discussed. The possible formation pathways for martian perchlorate are then explored and a possible mechanism for ongoing perchlorate formation on the martian surface is detailed. Perchlorate is shown to be formed upon exposure of chloride minerals, as well as of chlorite and chlorate salts, to current Mars relevant conditions including temperature, pressure, ultraviolet radiation and atmospheric composition. The implications of this ongoing perchlorate formation for the survival and detection of organics, the oxidizing nature of the soil, formation of liquid brines and recurring slope lineae are discussed. Further preliminary experiments have been conducted to investigate the effects of perchlorate formation on the survival and degradation of organic compounds.

  19. Some aspects of cesium deposition in Transilvania (Romania)

    International Nuclear Information System (INIS)

    Following the accident of the Chernobyl atomic electric power station, a great quantity of radionuclides (∼100MCi) escaped from the reactor. It was estimated that 13% of the inventory activity of cesium representing 1.5-2 MCi left the reactor. The radioactive deposits were very nonuniform for the same distance and in the same direction from Chernobyl nuclear center having a close dependence upon direction and speed of wind and pluviometric conditions. The rains, especially the storms, spectacularly increased the radioactive fallout. Although, for the first two-three days, subsequent to accident, the meteorological conditions were favorable for Romania, after April 29/30, because of the changing in the wind direction on SW (initial it was N and NW) the countries were on this direction - Romania, Bulgaria, Greece, former Yugoslavia - began to be intensely contaminated with radioactive fallout. In Romania, the radioactive cloud passing coincided with abundant rains, especially on the direction mentioned above. On this direction, the cesium deposits are of 8-2 times larger than other Romanian regions. The torrential rain which fell on May 1st 1986, in the western side of Cluj Napoca town caused an intense contamination especially with short-life isotopes as Te, I, Ba, La, Mo. Medium and long-life isotopes as Ru, Zr, Cs, Sr were present in large quantities in this area.too. For the total contribution the value obtained was 1130 kBq/m2, much larger than the average in Romania. This work presents data about cesium content of pollen samples gathered daily between 1-30 May 1986; cesium deposits in five areas and some measurements in connection with cesium mitigation in soils

  20. Perchlorate in Lake Water from an Operating Diamond Mine.

    Science.gov (United States)

    Smith, Lianna J D; Ptacek, Carol J; Blowes, David W; Groza, Laura G; Moncur, Michael C

    2015-07-01

    Mining-related perchlorate [ClO4(-)] in the receiving environment was investigated at the operating open-pit and underground Diavik diamond mine, Northwest Territories, Canada. Samples were collected over four years and ClO4(-) was measured in various mine waters, the 560 km(2) ultraoligotrophic receiving lake, background lake water and snow distal from the mine. Groundwaters from the underground mine had variable ClO4(-) concentrations, up to 157 μg L(-1), and were typically an order of magnitude higher than concentrations in combined mine waters prior to treatment and discharge to the lake. Snow core samples had a mean ClO4(-) concentration of 0.021 μg L(-1) (n=16). Snow and lake water Cl(-)/ClO4(-) ratios suggest evapoconcentration was not an important process affecting lake ClO4(-) concentrations. The multiyear mean ClO4(-) concentrations in the lake were 0.30 μg L(-1) (n = 114) in open water and 0.24 μg L(-1) (n = 107) under ice, much below the Canadian drinking water guideline of 6 μg L(-1). Receiving lake concentrations of ClO4(-) generally decreased year over year and ClO4(-) was not likely [biogeo]chemically attenuated within the receiving lake. The discharge of treated mine water was shown to contribute mining-related ClO4(-) to the lake and the low concentrations after 12 years of mining were attributed to the large volume of the receiving lake.

  1. Effects of prolonged exposure to perchlorate on thyroid and reproductive function in zebrafish

    Science.gov (United States)

    Mukhi, S.; Patino, R.

    2007-01-01

    The objectives of this study were to determine the effects of prolonged exposure to perchlorate on (1) thyroid status and reproductive performance of adult zebrafish (Danio rerio) and (2) F1 embryo survival and early larval development. Using a static-renewal procedure, mixed sex populations of adult zebrafish were exposed to 0, 10, and 100 mg/l nominal concentrations of waterborne perchlorate for 10 weeks. Thyroid histology was qualitatively assessed, and females and males were separated and further exposed to their respective treatments for six additional weeks. Eight females in each tank replicate (n = 3) were paired weekly with four males from the same respective treatment, and packed-egg (spawn) volume (PEV) was measured each of the last five weeks. At least once during weeks 14-16 of exposure, other end points measured included fertilization rate, fertilized egg diameter, hatching rate, standard length, and craniofacial development of 4-day-postfertilization larvae and thyroid hormone content of 3.5-h embryos and of exposed mothers. At 10 weeks of exposure, perchlorate at both concentrations caused thyroidal hypertrophy and colloid depletion. A marked reduction in PEV was observed toward the end of the 6-week spawning period, but fertilization and embryo hatching rates were unaffected. Fertilized egg diameter and larval length were increased by parental exposure to perchlorate. Larval head depth was unaffected but the forward protrusion of the lower jaw-associated cartilage complexes, Meckel's and ceratohyal, was decreased. Exposure to both concentrations of perchlorate inhibited whole-body thyroxine content in mothers and embryos, but triiodothyronine content was unchanged. In conclusion, prolonged exposure of adult zebrafish to perchlorate not only disrupts their thyroid endocrine system but also impairs reproduction and influences early F1 development. ?? 2007 Oxford University Press.

  2. Effects of larval-juvenile treatment with perchlorate and co-treatment with thyroxine on zebrafish sex ratios

    Science.gov (United States)

    Mukhi, S.; Torres, L.; Patino, R.

    2007-01-01

    The objective of this study was to determine the effect of larval-juvenile exposure to perchlorate, a thyroid hormone synthesis inhibitor, on the establishment of gonadal sex ratios in zebrafish. Zebrafish were exposed to untreated water or water containing perchlorate at 100 or 250 ppm for a period of 30 days starting at 3 days postfertilization (dpf). Recovery treatments consisted of a combination of perchlorate and exogenous thyroxine (T4; 10 nM). Thyroid histology was assessed at the end of the treatment period (33 dpf), and gonadal histology and sex ratios were determined in fish that were allowed an additional 10-day period of growth in untreated water. As expected, exposure to perchlorate caused changes in thyroid histology consistent with hypothyroidism and these effects were reversed by co-treatment with exogenous T4. Perchlorate did not affect fish survival but co-treatment with T4 induced higher mortality. However, relative to the corresponding perchlorate concentration, co-treatment with T4 caused increased mortality only at a perchlorate concentration of 100 ppm. Perchlorate alone or in the presence of T4 suppressed body length at 43 dpf relative to control values. Perchlorate exposure skewed the sex ratio toward female in a concentration-dependent manner, and co-treatment with T4 not only blocked the feminizing effect of perchlorate but also overcompensated by skewing the sex ratio towards male. Moreover, co-treatment with T4 advanced the onset of spermatogenesis in males. There was no clear association between sex ratios and larval survival or growth. We conclude that endogenous thyroid hormone plays a role in the establishment of gonadal sex phenotype during early development in zebrafish. ?? 2006 Elsevier Inc. All rights reserved.

  3. Microbial perchlorate reduction: A precise laboratory determination of the chlorine isotope fractionation and its possible biochemical basis

    Science.gov (United States)

    Ader, Magali; Chaudhuri, Swades; Coates, John D.; Coleman, Max

    2008-05-01

    Perchlorate-reducing bacteria fractionate chlorine stable isotopes giving a powerful approach to monitor the extent of microbial consumption of perchlorate in contaminated sites undergoing remediation or natural perchlorate containing sites. This study reports the full experimental data and methodology used to re-evaluate the chlorine isotope fractionation of perchlorate reduction in duplicate culture experiments of Azospira suillum strain PS at 37 °C (Δ 37Cl Cl --ClO 4-) previously reported, without a supporting data set by Coleman et al. [Coleman, M.L., Ader, M., Chaudhuri, S., Coates, J.D., 2003. Microbial Isotopic Fractionation of Perchlorate Chlorine. Appl. Environ. Microbiol. 69, 4997-5000] in a reconnaissance study, with the goal of increasing the accuracy and precision of the isotopic fractionation determination. The method fully described here for the first time, allows the determination of a higher precision Δ 37Cl Cl --ClO 4- value, either from accumulated chloride content and isotopic composition or from the residual perchlorate content and isotopic composition. The result sets agree perfectly, within error, giving average Δ 37Cl Cl --ClO 4- = - 14.94 ± 0.15‰. Complementary use of chloride and perchlorate data allowed the identification and rejection of poor quality data by applying mass and isotopic balance checks. This precise Δ 37Cl Cl --ClO 4- value can serve as a reference point for comparison with future in situ or microcosm studies but we also note its similarity to the theoretical equilibrium isotopic fractionation between a hypothetical chlorine species of redox state + 6 and perchlorate at 37 °C and suggest that the first electron transfer during perchlorate reduction may occur at isotopic equilibrium between an enzyme-bound chlorine and perchlorate.

  4. A low cost igniter utilizing an SCB and titanium sub-hydride potassium perchlorate pyrotechnic

    Science.gov (United States)

    Bickes, R. W., Jr.; Grubelich, M. C.; Hartman, J. K.; McCampbell, C. B.; Churchill, J. K.

    1994-01-01

    A conventional NSI (NASA Standard Initiator) normally employs a hot-wire ignition element to ignite ZPP (zirconium potassium perchlorate). With minor modifications to the interior of a header similar to an NSI device to accommodate an SCB (semiconductor bridge), a low cost initiator was obtained. In addition, the ZPP was replaced with THKP (titanium sub-hydride potassium perchlorate) to obtain increased overall gas production and reduced static-charge sensitivity. This paper reports on the all-fire and no-fire levels obtained and on a dual mix device that uses THKP as the igniter mix and a thermite as the output mix.

  5. Contact Electrification of Regolith Particles and Chloride Electrolysis: Synthesis of Perchlorates on Mars

    Science.gov (United States)

    Tennakone, K.

    2016-10-01

    Contact electrification of chloride-impregnated martian regolith particles due to eolian agitation and moisture condensation on coalesced oppositely charged grains may lead to spontaneous electrolysis that generates hypochlorite, chlorite, chlorate, and perchlorate with a concomitant reduction of water to hydrogen. This process is not curtailed even if moisture condenses as ice because chloride ionizes on the surface of ice. Limitations dictated by potentials needed for electrolysis and breakdown electric fields enable estimation of the required regolith grain size. The estimated dimension turns out to be of the same order of magnitude as the expected median size of martian regolith, and a simple calculation yields the optimum rate of perchlorate production.

  6. Distribution and retention of cesium and strontium in Swedish boreal forest ecosystems

    International Nuclear Information System (INIS)

    The retention and distribution of cesium, and to some extent strontium, in forest environments are being studied at three sites in Sweden. The main part of the cesium found in the soil was recovered in horizons rich in organic matter. The cesium was retained in the soil organic matter in a more or less extractable form. As different soil types have a different distribution pattern of organic matter, the distribution of cesium will depend on the forest soil type. The clay content in Swedish forest soils is, in general, low which will mitigate the retention of cesium in the soil mineral horizons. The cesium and strontium present in the trees was considered to be an effect of assimilation by the tissues in the canopy as well as by the roots. The redistribution of cesium within the trees was extensive which was considered to be the effect of a high mobility of cesium in the trees. The recovery of strontium-90 in pines, in relation to the deposition rate was higher compared to the relative recovery of cesium-137, 30 years after deposition. The cesium and strontium will remain in the forest environment for a considerable time but can be reduced by forest practice, by leaching out of the soil profile or by radioactive decay

  7. Development of a Reference Dose for Perchlorate: Current Issues and Status

    Science.gov (United States)

    Pleus, R. C.; Goodman, G.; Mattie, D. R.

    2000-01-01

    The perchlorate anion (ClO4) is typically manufactured as the ammonium salt. The most common use of ammonium perchlorate is in the aerospace program as a component of solid rocket fuel. The perchlorate anion is exceedingly stable under environmental conditions and has been found in ground and surface waters in CA, NV, UT, AZ, TX, AK, NY, MD, WV and FL. The National Center for Environmental Assessment (NCEA) of the U.S. Environmental Protection Agency (US EPA) is in the process of developing an oral reference dose (RfD) for perchlorate. An oral RfD is a body-weight-adjusted dose that can be consumed daily over an entire lifetime with the expectation of no adverse health effects. Once developed, the new RfD will be used by US EPA as the basis of a safe-drinking-water level (SDWL) guideline. US EPA and regional regulatory agencies will then jointly or separately propose clean-up action levels for ground and surface waters at contaminated sites. The toxicological database on CIO4- as of March 1997 was determined by an expert peer-review panel to be inadequate for the purpose of deriving an oral RfD. For example, little or no experimental data existed on the subchronic, reproductive, or developmental toxicity of perchlorate. To fill gaps in the toxicological database, eight animal studies were designed by a government-industry consortium that included US EPA and AFRL. These studies were performed in 1997-1998. It has been known for many years that in the thyroid, high doses of perchlorate block the function of iodide by competing for iodide binding sites. Perchlorate was used in the 1950s-60s as a treatment for Graves' disease (a hyperthyroid condition). Because of what was already known about the pharmacological mode of action of perchlorate, specific concerns addressed in the design of the recent animal studies included the potential for developmental toxicity, notably neurological development. Upon review of complete study reports from four of the studies and

  8. High Pressure Burn Rate Measurements on an Ammonium Perchlorate Propellant

    Energy Technology Data Exchange (ETDEWEB)

    Glascoe, E A; Tan, N

    2010-04-21

    High pressure deflagration rate measurements of a unique ammonium perchlorate (AP) based propellant are required to design the base burn motor for a Raytheon weapon system. The results of these deflagration rate measurements will be key in assessing safety and performance of the system. In particular, the system may experience transient pressures on the order of 100's of MPa (10's kPSI). Previous studies on similar AP based materials demonstrate that low pressure (e.g. P < 10 MPa or 1500 PSI) burn rates can be quite different than the elevated pressure deflagration rate measurements (see References and HPP results discussed herein), hence elevated pressure measurements are necessary in order understand the deflagration behavior under relevant conditions. Previous work on explosives have shown that at 100's of MPa some explosives will transition from a laminar burn mechanism to a convective burn mechanism in a process termed deconsolidative burning. The resulting burn rates that are orders-of-magnitude faster than the laminar burn rates. Materials that transition to the deconsolidative-convective burn mechanism at elevated pressures have been shown to be considerably more violent in confined heating experiments (i.e. cook-off scenarios). The mechanisms of propellant and explosive deflagration are extremely complex and include both chemical, and mechanical processes, hence predicting the behavior and rate of a novel material or formulation is difficult if not impossible. In this work, the AP/HTPB based material, TAL-1503 (B-2049), was burned in a constant volume apparatus in argon up to 300 MPa (ca. 44 kPSI). The burn rate and pressure were measured in-situ and used to calculate a pressure dependent burn rate. In general, the material appears to burn in a laminar fashion at these elevated pressures. The experiment was reproduced multiple times and the burn rate law using the best data is B = (0.6 {+-} 0.1) x P{sup (1.05{+-}0.02)} where B is the burn

  9. Kinetics of nitrate and perchlorate reduction in ion-exchange brine using the membrane biofilm reactor (MBfR).

    Science.gov (United States)

    Van Ginkel, Steven W; Ahn, Chang Hoon; Badruzzaman, Mohammad; Roberts, Deborah J; Lehman, S Geno; Adham, Samer S; Rittmann, Bruce E

    2008-09-01

    Several sources of bacterial inocula were tested for their ability to reduce nitrate and perchlorate in synthetic ion-exchange spent brine (30-45 g/L) using a hydrogen-based membrane biofilm reactor (MBfR). Nitrate and perchlorate removal fluxes reached as high as 5.4 g Nm(-2)d(-1) and 5.0 g ClO(4)m(-2)d(-1), respectively, and these values are similar to values obtained with freshwater MBfRs. Nitrate and perchlorate removal fluxes decreased with increasing salinity. The nitrate fluxes were roughly first order in H(2) pressure, but roughly zero-order with nitrate concentration. Perchlorate reduction rates were higher with lower nitrate loadings, compared to high nitrate loadings; this is a sign of competition for H(2). Nitrate and perchlorate reduction rates depended strongly on the inoculum. An inoculum that was well acclimated (years) to nitrate and perchlorate gave markedly faster removal kinetics than cultures that were acclimated for only a few months. These results underscore that the most successful MBfR bioreduction of nitrate and perchlorate in ion-exchange brine demands a well-acclimated inoculum and sufficient hydrogen availability.

  10. 高氯酸诺氟沙星铜(Ⅱ)%Norfloxacin Coppe(Ⅱ) Perchlorate

    Institute of Scientific and Technical Information of China (English)

    谢永荣; 叶琼; 熊仁根

    2004-01-01

    The hydrothermal treatment of Cu(ClO4)2·6H2O and Norfloxacin (H-Norf) afforded [Cu(H-Noff)2(ClO4)2] (1) in which center Cu has a square planar geometry while perchlorate just acts as charge balance anions. CCDC:140821.

  11. (Per)chlorate reduction by an acetogenic bacterium, Sporomusa sp., isolated from an underground gas storage.

    KAUST Repository

    Balk, Melike

    2010-08-03

    A mesophilic bacterium, strain An4, was isolated from an underground gas storage reservoir with methanol as substrate and perchlorate as electron acceptor. Cells were Gram-negative, spore-forming, straight to curved rods, 0.5-0.8 microm in diameter, and 2-8 microm in length, growing as single cells or in pairs. The cells grew optimally at 37 degrees C, and the pH optimum was around 7. Strain An4 converted various alcohols, organic acids, fructose, acetoin, and H(2)/CO(2) to acetate, usually as the only product. Succinate was decarboxylated to propionate. The isolate was able to respire with (per)chlorate, nitrate, and CO(2). The G+C content of the DNA was 42.6 mol%. Based on the 16S rRNA gene sequence analysis, strain An4 was most closely related to Sporomusa ovata (98% similarity). The bacterium reduced perchlorate and chlorate completely to chloride. Key enzymes, perchlorate reductase and chlorite dismutase, were detected in cell-free extracts.

  12. The Impact of Temperature on Anaerobic Biological Perchlorate Removal and Aerobic Polishing of the Effluent

    Science.gov (United States)

    This abstract describes a pilot-scale evaluation of anaerobic biological perchlorate (C1O4) removal followed by aerobic effluent polishing. The anaerobic biological contactor operated for 3.5 years. During that period, two effluent polishing evaluations, lasting 311 an...

  13. The Impact of Temperature on Anaerobic Biological Perchlorate Removal and Aerobic Polishing of the Effluent - paper

    Science.gov (United States)

    This abstract describes a pilot-scale evaluation of anaerobic biological perchlorate (C1O4) removal followed by aerobic effluent polishing. The anaerobic biological contactor operated for 3.5 years. During that period, two effluent polishing evaluations, lasting 311 an...

  14. Regioselective iodination of aromatic compounds with potassium iodide in the presence of benzyltriphenylphosphonium perchlorate

    Institute of Scientific and Technical Information of China (English)

    Jalal Albadi; Masoumeh Abedini; Nasir Iravani

    2012-01-01

    A simple and efficient method for the selective iodination of various aromatic compounds by using potassium iodide in the presence of benzyltriphenylphosphonium perchlorate,is reported.This method provides several advantages such as good selectivity between ortho and para positions of aromatic compounds and high yields of the products.

  15. A STUDY ON THE ACCUMULATION OF PERCHLORATE IN YOUNG HEAD LETTUCE

    Science.gov (United States)

    The overall objective of this study was to demonstrate in a greenhouse study the potential for incorporation of perchlorate from aqueous solutions of 10, 50, 100, 500, 1,000, 5,000, and 10,000 ppb into an agricultural food crop (lettuce; Lactuca sativa), which is typically grown ...

  16. Preparation and Analysis of Solid Solutions in the Potassium Perchlorate-Permanganate System.

    Science.gov (United States)

    Johnson, Garrett K.

    1979-01-01

    Describes an experiment, designed for and tested in an advanced inorganic laboratory methods course for college seniors and graduate students, that prepares and analyzes several samples in the nearly ideal potassium perchlorate-permanganate solid solution series. The results are accounted for by a theoretical treatment based upon aqueous…

  17. Double-Polymer-Modified Pencil Lead for Stripping Voltammetry of Perchlorate in Drinking Water

    Science.gov (United States)

    Izadyar, Anahita; Kim, Yushin; Ward, Michelle M.; Amemiya, Shigeru

    2012-01-01

    The inexpensive and disposable electrode based on a double-polymer-modified pencil lead is proposed for upper-division undergraduate instrumental laboratories to enable the highly sensitive detection of perchlorate. Students fabricate and utilize their own electrodes in the 3-4 h laboratory session to learn important concepts and methods of…

  18. Reactive Transport Model of Sulfur Cycling as Impacted by Perchlorate and Nitrate Treatments.

    Science.gov (United States)

    Cheng, Yiwei; Hubbard, Christopher G; Li, Li; Bouskill, Nicholas; Molins, Sergi; Zheng, Liange; Sonnenthal, Eric; Conrad, Mark E; Engelbrektson, Anna; Coates, John D; Ajo-Franklin, Jonathan B

    2016-07-01

    Microbial souring in oil reservoirs produces toxic, corrosive hydrogen sulfide through microbial sulfate reduction, often accompanying (sea)water flooding during secondary oil recovery. With data from column experiments as constraints, we developed the first reactive-transport model of a new candidate inhibitor, perchlorate, and compared it with the commonly used inhibitor, nitrate. Our model provided a good fit to the data, which suggest that perchlorate is more effective than nitrate on a per mole of inhibitor basis. Critically, we used our model to gain insight into the underlying competing mechanisms controlling the action of each inhibitor. This analysis suggested that competition by heterotrophic perchlorate reducers and direct inhibition by nitrite produced from heterotrophic nitrate reduction were the most important mechanisms for the perchlorate and nitrate treatments, respectively, in the modeled column experiments. This work demonstrates modeling to be a powerful tool for increasing and testing our understanding of reservoir-souring generation, prevention, and remediation processes, allowing us to incorporate insights derived from laboratory experiments into a framework that can potentially be used to assess risk and design optimal treatment schemes. PMID:27267666

  19. DISTRIBUTION OF PERCHLORATE IN SAMPLES OF SODIUM NITRATE (CHILE SALTPETER) FERTILIZER DERIVED FROM NATURAL CALICHE

    Science.gov (United States)

    Two lots of sodium nitrate fertilizer derived from Chilean caliche were analyzed to determine the distribution of perchlorate throughout the material. Although our samples represent a limited amount, we found that distribution was essentially homogeneous in any 100-g portion. Whe...

  20. Cesium-137, a drama recounted; Cesio-137, um drama recontado

    Energy Technology Data Exchange (ETDEWEB)

    Vieira, Suzane de Alencar

    2013-01-15

    The radiological accident with Cesium-137, which started on Goiania in 1987, did not stop with the end of radiological contamination and continues in a judicial, scientific and narrative process of identification and recognition of new victims. The drama occupies a central place on the dynamics of radiological event, as it extends its limits, inflects its intensity and updates the event. As a narrative of the event, the ethnography incorporates and brings up to date the drama as an analysis landmark and the description of the theme as it is absorbed by a dramatic process. Cesium-137, a drama recounted is a textual experimentation based on real events and characters picked out from statements reported in various narratives about the radiological accident. (author)

  1. Trapping and cooling cesium atoms in a speckle field

    International Nuclear Information System (INIS)

    We present the results of two experiments where cold cesium atoms are trapped in a speckle field. In the first experiment, a YAG laser creates the speckle pattern and induces a far-detuned dipole potential which is a nearly-conservative potential. Localization of atoms near the intensity maxima of the speckle field is observed. In a second experiment we use two counterpropagating laser beams tuned close to a resonance line of cesium and in the lin perpendicular to lin configuration, one of them being modulated by a holographic diffuser that creates the speckle field. Three-dimensional cooling is observed. Variations of the temperature and of the spatial diffusion coefficient with the size of a speckle grain are presented. (orig.)

  2. Kelvin Probe Studies of Cesium Telluride Photocathode for AWA Photoinjector

    CERN Document Server

    Wisniewski, Eric; Yusof, Zikri; Spentzouris, Linda; Terry, Jeff; Harkay, Katherine

    2012-01-01

    Cesium telluride is an important photocathode as an electron source for particle accelerators. It has a relatively high quantum efficiency (>1%), is sufficiently robust in a photoinjector, and has a long lifetime. This photocathode is grown in-house for a new Argonne Wakefield Accelerator (AWA) beamline to produce high charge per bunch (~50 nC) in a long bunch train. Here, we present a study of the work function of cesium telluride photocathode using the Kelvin Probe technique. The study includes an investigation of the correlation between the quantum efficiency and the work function, the effect of photocathode aging, the effect of UV exposure on the work function, and the evolution of the work function during and after photocathode rejuvenation via heating.

  3. Cesium exchange reaction on natural and modified clinoptilolite zeolites

    International Nuclear Information System (INIS)

    Cesium cation exchange reaction with K, Na, Ca and Mg ions on natural and modified clinoptilolite has been studied. Batch cation-exchange experiments were performed by placing 0.5 g of clinoptilolite into 10 ml or 20 ml of 1 x 10-3M CsCl solution for differing times. Two type deposits of clinoptilolite zeolites from, Nizny Hrabovec (NH), Slovakia and Metaxades (MX), Greece were used for ion-exchange study. The distribution coefficient (Kd) and sorption capacity (Γ) were evaluated. For the determination of K, Na, Ca and Mg isotachophoresis method, the most common cations in exchange reaction was used. Cesium sorption was studied using 137Cs tracer and measured by γ-spectrometry. (author)

  4. Spectrally selective optical pumping in Doppler-broadened cesium atoms

    International Nuclear Information System (INIS)

    The D1 line spectrally selective pumping process in Doppler-broadened cesium is analyzed by solving the optical Bloch equations. The process, described by a three-level model with the Λ scheme, shows that the saturation intensity of broadened atoms is three orders of magnitude larger than that of resting atoms. The |Fg = 3> → |Fe = 4> resonance pumping can result in the ground state |Fg = 4, mF = 4> sublevel having a maximum population of 0.157 and the population difference would be about 0.01 in two adjacent magnetic sublevels of the hyperfine (HF) state Fg = 4. To enhance the anisotropy in the ground state, we suggest employing dichromatic optical HF pumping by adding a laser to excite D1 line |Fg = 4> → |Fe = 3> transition, in which the cesium magnetometer sensitivity increases by half a magnitude and is unaffected by the nonlinear Zeeman effect even in Earth's average magnetic field. (atomic and molecular physics)

  5. Fiber laser system for cesium and rubidium atom interferometry

    CERN Document Server

    Diboune, Clément; Bidel, Yannick; Cadoret, Malo; Bresson, Alexandre

    2016-01-01

    We present an innovative fiber laser system for both cesium and rubidium manipulation. The architecture is based on frequency conversion of two lasers at 1560 nm and 1878 nm. By taking advantage of existing fiber components at these wavelengths, we demonstrate an all fiber laser system delivering 350 mW at 780 nm for rubidium and 210 mW at 852 nm for cesium. This result highlights the promising nature of such laser system especially for Cs manipulation for which no fiber laser system has been reported. It offers new perspectives for the development of atomic instruments dedicated to onboard applications and opens the way to a new generation of atom interferometers involving three atomic species $^{85}$Rb, $^{87}$Rb and $^{133}$Cs for which we propose an original laser architecture.

  6. Systematics of Natural Perchlorate in Precipitation, Soils, and Plants at the Amargosa Desert Research Site, Nye County, Nevada

    Science.gov (United States)

    Andraski, B. J.; Stonestrom, D. A.; Jackson, W. A.; Rajagopalan, S.; Taylor, E. M.

    2007-12-01

    Naturally occurring perchlorate is known to be associated with nitrate deposits of the hyperarid Atacama Desert in Chile, and recent large-scale sampling has identified a substantial reservoir (up to 1 kg/ha) of natural perchlorate in diverse unsaturated zones of the arid and semiarid Southwestern United States (Rao et al., 2007, ES&T, DOI: 10.1021/es062853i). The objective of the Amargosa Desert work is to develop a better understanding of the deposition, accumulation, and biological cycling of perchlorate in arid environments. Occurrence of perchlorate was evaluated by sampling shallow soil profiles up to 3 m in depth at four different locations and at two different time periods, and by sampling dominant plant species growing near the subsurface profiles. Deposition of perchlorate was evaluated by analyzing both bulk deposition (precipitation plus dry fall, collected under oil) collected on site and wet deposition samples collected by the National Atmospheric Deposition program at a nearby site. Soil samples and atmospheric-deposition samples were tested for both perchlorate (ClO4- ) and major anions. Perchlorate concentrations (0.2-20 µg/kg) were variable with depth in soil profiles and generally correlated most highly with chloride (Cl-) and nitrate (NO3-), although the intensity of these relations differed among profiles. Plant concentrations were generally above 1 mg/kg, suggesting ClO4- accumulation. Concentrations of ClO4- were generally much greater in total deposition than wet deposition samples, indicating a substantial dryfall component of meteoric deposition. This presentation will present the mass distribution and variability of perchlorate in bulk deposition, soils, and plants. Reasons for observed relations between subsurface concentrations of perchlorate and other anions will be explored.

  7. Fractionation of stable isotopes in perchlorate and nitrate during in situ biodegradation in a sandy aquifer

    Science.gov (United States)

    Hatzinger, P.B.; Böhlke, J.K.; Sturchio, N.C.; Gu, B.; Heraty, L.J.; Borden, R.C.

    2009-01-01

    Environmental context. Perchlorate (ClO4-) and nitrate (NO3-) are common co-contaminants in groundwater, with both natural and anthropogenic sources. Each of these compounds is biodegradable, so in situ enhanced bioremediation is one alternative for treating them in groundwater. Because bacteria typically fractionate isotopes during biodegradation, stable isotope analysis is increasingly used to distinguish this process from transport or mixing-related decreases in contaminant concentrations. However, for this technique to be useful in the field to monitor bioremediation progress, isotope fractionation must be quantified under relevant environmental conditions. In the present study, we quantify the apparent in situ fractionation effects for stable isotopes in ClO4- (Cl and O) and NO3- (N and O) resulting from biodegradation in an aquifer. Abstract. An in situ experiment was performed in a shallow alluvial aquifer in Maryland to quantify the fractionation of stable isotopes in perchlorate (Cl and O) and nitrate (N and O) during biodegradation. An emulsified soybean oil substrate that was previously injected into this aquifer provided the electron donor necessary for biological perchlorate reduction and denitrification. During the field experiment, groundwater extracted from an upgradient well was pumped into an injection well located within the in situ oil barrier, and then groundwater samples were withdrawn for the next 30 h. After correction for dilution (using Br- as a conservative tracer of the injectate), perchlorate concentrations decreased by 78% and nitrate concentrations decreased by 82% during the initial 8.6 h after the injection. The observed ratio of fractionation effects of O and Cl isotopes in perchlorate (18O/37Cl) was 2.6, which is similar to that observed in the laboratory using pure cultures (2.5). Denitrification by indigenous bacteria fractionated O and N isotopes in nitrate at a ratio of ???0.8 (18O/15N), which is within the range of values

  8. Studies on the Separation of Cesium From Fission Products

    Institute of Scientific and Technical Information of China (English)

    QIANLi-juan; ZHANGSheng-dong; GUOJing-ru; CUIAn-zhi; YANGLei; WUWang-suo

    2003-01-01

    135Cs is a long-life fission product. When measuring its thermal cross section, we must separate radiochemical purity cesium from fission products. Except for decontaminating radio- nuclides, others which can be activated must be avoided to come into solution. So ion exchanger is used. Inorganic ion exchangers have received increased attention because of their high resistance to radiation and their very efficient separation of alkali metal ions.

  9. Optimized production of a cesium Bose-Einstein condensate

    OpenAIRE

    Kraemer, Tobias; Herbig, Jens; Mark, Michael; Weber, Tino; Chin, Cheng; Naegerl, Hanns-Christoph; Grimm, Rudolf

    2004-01-01

    We report on the optimized production of a Bose-Einstein condensate of cesium atoms using an optical trapping approach. Based on an improved trap loading and evaporation scheme we obtain more than $10^5$ atoms in the condensed phase. To test the tunability of the interaction in the condensate we study the expansion of the condensate as a function of scattering length. We further excite strong oscillations of the trapped condensate by rapidly varying the interaction strength.

  10. Radioactive cesium. Dynamics and transport in forestal food-webs

    International Nuclear Information System (INIS)

    This report summarises results from a radioecological study during 1994-1995 concerning turnover, redistribution and loss of radioactive Cesium (134 and 137) in boreal forest ecosystems, as well as uptake and transfer in important food-chains over moose, vole and vegetation. The basis for this report are 9 publications published 1994-95. These reports are presented in summary form. 9 refs, 17 figs

  11. Electrically switched cesium ion exchange. FY 1997 annual report

    International Nuclear Information System (INIS)

    This paper describes the Electrically Switched Ion Exchange (ESIX) separation technology being developed as an alternative to ion exchange for removing radionuclides from high-level waste. Progress in FY 1997 for specific applications of ESIX is also outlined. The ESIX technology, which combines ion exchange and electrochemistry, is geared toward producing electroactive films that are highly selective, regenerable, and long lasting. During the process, ion uptake and elution can be controlled directly by modulating the potential of an ion exchange film that has been electrochemically deposited onto a high surface area electrode. This method adds little sodium to the waste stream and minimizes the secondary wastes associated with traditional ion exchange techniques. Development of the ESIX process is well underway for cesium removal using ferrocyanides as the electroactive films. Films having selectivity for perrhenate (a pertechnetate surrogate) over nitrate also have been deposited and tested. Based on the ferrocyanide film capacity, stability, rate of uptake, and selectivity shown during performance testing, it appears possible to retain a consistent rate of removal and elute cesium into the same elution solution over several load/unload cycles. In batch experiments, metal hexacyanoferrate films showed high selectivities for cesium in concentrated sodium solutions. Cesium uptake was unaffected by Na/Cs molar ratios of up to 2 x 104 , and reached equilibrium within 18 hours. During engineering design tests using 60 pores per inch, high surface area nickel electrodes, nickel ferrocyanide films displayed continued durability. losing less than 20% of their capacity after 1500 load/unload cycles. Bench-scale flow system studies showed no change in capacity or performance of the ESIX films at a flow rate up to 13 BV/h, the maximum flow rate tested, and breakthrough curves further supported once-through waste processing. 9 refs., 24 figs

  12. Corrections to our results for optical nanofiber traps in Cesium

    CERN Document Server

    Ding, D; Choi, K S; Kimble, H J

    2012-01-01

    Several errors in Refs. [1, 2] are corrected related to the optical trapping potentials for a state-insensitive, compensated nanofiber trap for the D2 transition of atomic Cesium. Section I corrects our basic formalism in Ref. [1] for calculating dipole-force potentials. Section II corrects erroneous values for a partial lifetime and a transition wavelength in Ref. [1]. Sections III and IV present corrected figures for various trapping configurations considered in Refs. [1] and [2], respectively.

  13. Test procedures and instructions for Hanford complexant concentrate supernatant cesium removal using CST

    Energy Technology Data Exchange (ETDEWEB)

    Hendrickson, D.W.

    1997-01-08

    This document provides specific test procedures and instructions to implement the test plan for the preparation and conduct of a cesium removal test, using Hanford Complexant Concentrate supernatant liquor from tank 241-AN-107, in a bench-scale column. The cesium sorbent to be tested is crystalline silicotitanate. The test plan for which this provides instructions is WHC-SD-RE-TP-023, Hanford Complexant Concentrate Supernatant Cesium Removal Test Plan.

  14. Test procedures and instructions for Hanford tank waste supernatant cesium removal

    Energy Technology Data Exchange (ETDEWEB)

    Hendrickson, D.W., Westinghouse Hanford

    1996-05-31

    This document provides specific test procedures and instructions to implement the test plan for the preparation and conduct of a cesium removal test using Hanford Double-Shell Slurry Feed supernatant liquor from tank 251-AW-101 in a bench-scale column.Cesium sorbents to be tested include resorcinol-formaldehyde resin and crystalline silicotitanate. The test plan for which this provides instructions is WHC-SD-RE-TP-022, Hanford Tank Waste Supernatant Cesium Removal Test Plan.

  15. MODELING RESULTS FROM CESIUM ION EXCHANGE PROCESSING WITH SPHERICAL RESINS

    Energy Technology Data Exchange (ETDEWEB)

    Nash, C.; Hang, T.; Aleman, S.

    2011-01-03

    Ion exchange modeling was conducted at the Savannah River National Laboratory to compare the performance of two organic resins in support of Small Column Ion Exchange (SCIX). In-tank ion exchange (IX) columns are being considered for cesium removal at Hanford and the Savannah River Site (SRS). The spherical forms of resorcinol formaldehyde ion exchange resin (sRF) as well as a hypothetical spherical SuperLig{reg_sign} 644 (SL644) are evaluated for decontamination of dissolved saltcake wastes (supernates). Both SuperLig{reg_sign} and resorcinol formaldehyde resin beds can exhibit hydraulic problems in their granular (nonspherical) forms. SRS waste is generally lower in potassium and organic components than Hanford waste. Using VERSE-LC Version 7.8 along with the cesium Freundlich/Langmuir isotherms to simulate the waste decontamination in ion exchange columns, spherical SL644 was found to reduce column cycling by 50% for high-potassium supernates, but sRF performed equally well for the lowest-potassium feeds. Reduced cycling results in reduction of nitric acid (resin elution) and sodium addition (resin regeneration), therefore, significantly reducing life-cycle operational costs. These findings motivate the development of a spherical form of SL644. This work demonstrates the versatility of the ion exchange modeling to study the effects of resin characteristics on processing cycles, rates, and cold chemical consumption. The value of a resin with increased selectivity for cesium over potassium can be assessed for further development.

  16. Contribution of tap water to chlorate and perchlorate intake: a market basket study.

    Science.gov (United States)

    Asami, Mari; Yoshida, Nobue; Kosaka, Koji; Ohno, Koichi; Matsui, Yoshihiko

    2013-10-01

    The contributions of water to total levels of chlorate and perchlorate intake were determined using food and water samples from a market basket study from 10 locations in Japan between 2008 and 2009. Foods were categorized into 13 groups and analyzed along with tap water. The average total chlorate intake was 333 (min. 193-max. 486) μg/day for samples cooked with tap water. The contribution of tap water to total chlorate intake was as high as 47%-58%, although total chlorate intake was less than 32% of the tolerable daily intake, 1500 μg/day for body weight of 50 kg. For perchlorate, daily intake from water was 0.7 (0.1-4.4) μg/day, which is not high compared to the average total intake of 14 (2.5-84) μg/day, while the reference dose (RfD) is 35 μg/day and the provisional maximum tolerable daily intake (PMTDI) is 500 μg/day for body weight of 50 kg. The highest intake of perchlorate was 84 μg/day, where concentrations in foods were high, but not in water. The contribution of water to total perchlorate intake ranged from 0.5% to 22%, while the ratio of highest daily intake to RfD was 240% and that to PMTDI was 17%. Eight baby formulas were also tested--total chlorate and perchlorate intakes were 147 (42-332) μg/day and 1.11 (0.05-4.5) μg/day, respectively, for an ingestion volume of 1 L/day if prepared with tap water.

  17. Cesium Toxicity Alters MicroRNA Processing and AGO1 Expressions in Arabidopsis thaliana.

    Directory of Open Access Journals (Sweden)

    Il Lae Jung

    Full Text Available MicroRNAs (miRNAs are short RNA fragments that play important roles in controlled gene silencing, thus regulating many biological processes in plants. Recent studies have indicated that plants modulate miRNAs to sustain their survival in response to a variety of environmental stimuli, such as biotic stresses, cold, drought, nutritional starvation, and toxic heavy metals. Cesium and radio-cesium contaminations have arisen as serious problems that both impede plant growth and enter the food chain through contaminated plants. Many studies have been performed to define plant responses against cesium intoxication. However, the complete profile of miRNAs in plants during cesium intoxication has not been established. Here we show the differential expression of the miRNAs that are mostly down-regulated during cesium intoxication. Furthermore, we found that cesium toxicity disrupts both the processing of pri-miRNAs and AGONOUTE 1 (AGO1-mediated gene silencing. AGO 1 seems to be especially destabilized by cesium toxicity, possibly through a proteolytic regulatory pathway. Our study presents a comprehensive profile of cesium-responsive miRNAs, which is distinct from that of potassium, and suggests two possible mechanisms underlying the cesium toxicity on miRNA metabolism.

  18. Laboratory plant for the separation of cesium from waste solutions of the PUREX process

    International Nuclear Information System (INIS)

    A laboratory plant for the separation of cesium from a fission product waste solution of the fuel reprocessing is described. The plant consists of two stages. In the first stage cesium is adsorbed on ammonium molybdatophosphate (AMP). Then the adsorbent is dissolved. From the solution cesium is adsorbed on a cationic ion exchanger in the second stage. Then AMP can be reproduced from this solution. For the elution of cesium in the second stage a NH4NO3 solution (3 m) is used. Flow sheet, construction and the control device of the plant are described and the results of tests with a model solution are given. (author)

  19. Structure of cesium loaded iron phosphate glasses: An infrared and Raman spectroscopy study

    International Nuclear Information System (INIS)

    The structure of cesium loaded iron phosphate glasses (IPG) was investigated using infrared and Raman spectroscopy. The spectra of the cesium doped samples revealed a structural modification of the parent glass owing to the incorporation of cesium. The structural changes could be correlated with the variation observed in the glass transition temperature of these glasses. Increased Cs-mediated cationic cross linking appears to be the reason for the initial rise in glass transition temperature up to 21 mol% Cs2O in IPG; while, breakdown of the phosphate network with increasing cesium content, brings down the glass transition temperature.

  20. Mobility of cesium through the Callovo-Oxfordian claystones under partially saturated conditions

    International Nuclear Information System (INIS)

    The diffusion of cesium was studied in an unsaturated core of Callovo-Oxfordian claystone, which is a potential host rock for retrievable disposal of high-level radioactive wastes. In-diffusion laboratory experiments were performed on rock samples with water saturation degrees ranging from 81% to 100%. The analysis of both cesium concentration monitoring in the source reservoir and postmortem cesium rock concentration profile of the samples was carried out using a chemical-transport code where the sorption of cesium was described by a multi-site ion-exchange model. The results showed that cesium exhibited a clear trend related to the saturation degree of the sample. The more dehydrated the rock sample, the slower the decrease of cesium concentration, and the thinner the penetration depth of cesium was. The effective diffusion coefficient (De) for cesium decreased from 18.5 *10-11 m2 s-1 at full-saturation to 0.3 * 10-11 m2 s-1 for the more dehydrated sample. This decrease is almost 1 order of magnitude higher than that for tritiated water (HTO), although a similar behavior could have been expected, since cesium is known to diffuse in the same parts of the pore space as HTO in fully saturated claystones. (authors)

  1. Cesium transport in Four Mile Creek of the Savannah River Plant

    International Nuclear Information System (INIS)

    The behavior of a large radioactive cesium release to a Savannah River Plant (SRP) stream was examined using a stable cesium release to Four Mile Creek. Measurements following the release show that most of the cesium released was transported downstream; however, sorption and desorption decreased the maximum concentration and increased the travel time and duration, relative to a dye tracer, at sampling stations downstream. The study was made possible by the development of an analytical technique using ammonium molybdophosphate and neutron activation that permitted the measurement of stable cesium concentrations as low as 0.2 μg/L

  2. Preparation of Modified Kaolin Filler with Cesium and Its Application in Security Paper

    OpenAIRE

    Houssni El-Saied; Samya El-Sherbiny; Omnia Ali; Wafaa El-Saied; Said Rohyem

    2013-01-01

    In this study, cesium was added intentionally during paper manufacture for protecting the papers against forgery and counterfeiting by sorbing cesium ions (Cs+) on kaolin, used as special filler in papermaking. The sorption of cesium from aqueous solution by kaolin was studied as a function of pH, shaking time, cesium initial concentration, and mass of kaolin using batch technique. The results showed that a solution containing 10 mg/L Cs+ and 250 mg of kaolin at pH 6 can be used to modify the...

  3. Dissimilatory perchlorate reduction linked to aerobic methane oxidation via chlorite dismutase

    Science.gov (United States)

    Oremland, R. S.; Baesman, S. M.; Miller, L. G.

    2013-12-01

    The presence of methane (CH4) in the atmosphere of Mars is controversial yet the evidence has aroused scientific interest, as CH4 could be a harbinger of extant or extinct microbial life. There are various oxidized compounds present on the surface of Mars that could serve as electron acceptors for the anaerobic oxidation of CH4, including perchlorate (ClO4-). We examined the role of perchlorate, chlorate (ClO3-) and chlorite (ClO2-) as oxidants linked to CH4 oxidation. Dissimilatory perchlorate reduction begins with reduction of ClO4- to ClO2- and ends with dismutation of chlorite to yield chloride (Cl-) and molecular oxygen (O2). We explored the potential for aerobic CH4 oxidizing bacteria to couple with oxygen derived from chlorite dismutation during dissimilatory perchlorate reduction. Methane (0.2 kPa) was completely removed within several days from the N2-flushed headspace above cell suspensions of methanotrophs (Methylobacter albus strain BG8) and perchlorate reducing bacteria (Dechloromonas agitata strain CKB) in the presence of 5 mM ClO2-. Similar rates of CH4 consumption were observed for these mixed cultures whether they were co-mingled or segregated under a common headspace, indicating that direct contact of cells was not required for methane consumption to occur. We also observed complete removal of 0.2 kPa CH4 in bottles containing dried soil (enriched in methanotrophs by CH4 additions over several weeks) and D. agitata CKB and in the presence of 10 mM ClO2-. This soil (seasonally exposed sediment) collected from the shoreline of a freshwater lake (Searsville Lake, CA) demonstrated endogenous CH4 uptake as well as perchlorate, chlorate and chlorite reduction/dismutation. However, these experiments required physical separation of soil from the aqueous bacterial culture to allow for the partitioning of O2 liberated from chlorite dismutation into the shared headspace. Although dissimilatory reduction of ClO4- and ClO3- could be inferred from the

  4. Reaction of Elemol with Acetic acid –Perchloric acid: Characterization of a novel oxide and (+)-β-cyperone

    Digital Repository Service at National Institute of Oceanography (India)

    Wahidullah, S.; Govenkar, M.B.; Paknikar, S.K.

    The minor unidentified compounds of acetic acid- perchloric acid dehydration of elemol (1) have been fully characterized. The structure and relative stereochemistry as shown in (2) of the less polar fragrant compound named as elemoxide was deduced...

  5. In situ bioremediation of nitrate and perchlorate in vadose zone soil for groundwater protection using gaseous electron donor injection technology.

    Science.gov (United States)

    Evans, Patrick J; Trute, Mary M

    2006-12-01

    When present in the vadose zone, potentially toxic nitrate and perchlorate anions can be persistent sources of groundwater contamination. Gaseous electron donor injection technology (GEDIT), an anaerobic variation of petroleum hydrocarbon bioventing, involves injecting electron donor gases, such as hydrogen or ethyl acetate, into the vadose zone, to stimulate biodegradation of nitrate and perchlorate. Laboratory microcosm studies demonstrated that hydrogen and ethanol promoted nitrate and perchlorate reduction in vadose zone soil and that moisture content was an important factor. Column studies demonstrated that transport of particular electron donors varied significantly; ethyl acetate and butyraldehyde were transported more rapidly than butyl acetate and ethanol. Nitrate removal in the column studies, up to 100%, was best promoted by ethyl acetate. Up to 39% perchlorate removal was achieved with ethanol and was limited by insufficient incubation time. The results demonstrate that GEDIT is a promising remediation technology warranting further validation.

  6. Potential Influence of Perchlorate on Heavy Metals and Organic Carbon in Serpentine Soil; Implications for Martian Regolith

    Science.gov (United States)

    Oze, C.; Kumarathilaka, P. R.; Indraratne, S.; Vithanage, M. S.

    2015-12-01

    Prasanna Kumarathilaka Chemical and Environmental Systems Modeling Research Group, National Institute of Fundamental Studies, Kandy, Sri LankaPerchlorate (ClO4-) concentrations as high as 1 Wt.% have been reported in Martian regolith. Perchlorate is a strong oxidizer capable of accelerating heavy and/or trace metal release into regolith/soil and reacting with organic matter/compounds (if present). Here, we assess interactions between perchlorate and an analogous Martian regolith (i.e., serpentine soil) to simulate and understand the fate of Mn, Ni and Co and organic carbon. Pre-characterized serpentine soil collected from Sri Lanka was used for this study. Incubation experiments were performed with three perchlorate concentrations (1, 0.75 and 0.5 w/w) and sequential and single extractions assessed solid phase metal fractionation in serpentine sediments after 3 weeks and 1 year, respectively. Additionally, total organic carbon (TOC) of the residues were analyzed. These experiments demonstrate a high release of Mn compared to Ni and Co. Metal concentrations in exchangeable and bioavailable fractions increased with increasing perchlorate concentrations. Exchangeable Ni, Mn and Co increased 5.9, 69.6 and 44.6% and bioavailable Ni, Mn and Co increased 5.5, 92.3 and 72.8%, respectively, after 1 year compared to 3 weeks. Additionally, TOC decreased with increasing perchlorate concentration. For example, TOC decreased by 14.3% after 1 year compared to a 3 week incubation period. Overall, this study confirms the accelerated release of metals and the removal of organic carbon with increasing perchlorate concentrations. Furthermore, this study illustrates how perchlorate may present additional challenges to current Martian life studies and the future human habitation of Mars.Prasanna Kumarathilaka Chemical and Environmental Systems Modeling Research Group, National Institute of Fundamental Studies, Kandy, Sri LankaPerchlorate (ClO4-) concentrations as high as 1 Wt.% have

  7. Perchlorate content of plant foliage reflects a wide range of species-dependent accumulation but not ozone-induced biosynthesis

    International Nuclear Information System (INIS)

    Perchlorate (ClO4−) interferes with uptake of iodide in humans. Emission inventories do not explain observed distributions. Ozone (O3) is implicated in the natural origin of ClO4−, and has increased since pre-industrial times. O3 produces ClO4−in vitro from Cl−, and plant tissues contain Cl− and redox reactions. We hypothesize that O3 exposure may induce plant synthesis of ClO4−. We exposed contrasting crop species to environmentally relevant O3 concentrations. In the absence of O3 exposure, species exhibited a large range of ClO4− accumulation but there was no relationship between leaf ClO4− and O3, whether expressed as exposure or cumulative flux (dose). Older, senescing leaves accumulated more ClO4− than younger leaves. O3 exposed vegetation is not a source of environmental ClO4−. There was evidence of enhanced ClO4− content in the soil surface at the highest O3 exposure, which could be a significant contributor to environmental ClO4−. -- Highlights: • Exposure to ozone in crop species does not induce accumulation nor biosynthesis of perchlorate. • Older leaves accumulate more perchlorate than younger leaves. • Soil surface may accumulate perchlorate following exposure to ozone. • Species differ greatly in accumulation of perchlorate from the rhizosphere, independent of ozone. • Ozone exposed vegetation is not a candidate source of environmental perchlorate. -- Exposure of crop species to ozone did not lead to biosynthesis or greater accumulation of foliar perchlorate. Older leaves accumulated more perchlorate than younger leaves

  8. Oxygen and chlorine isotopic fractionation during perchlorate biodegradation: Laboratory results and implications for forensics and natural attenuation studies

    Science.gov (United States)

    Sturchio, N.C.; Böhlke, J.K.; Beloso, A.D.; Streger, S.H.; Heraty, L.J.; Hatzinger, P.B.

    2007-01-01

    Perchlorate is a widespread environmental contaminant having both anthropogenic and natural sources. Stable isotope ratios of O and Cl in a given sample of perchlorate may be used to distinguish its source(s). Isotopic ratios may also be useful for identifying the extent of biodegradation of perchlorate, which is critical for assessing natural attenuation of this contaminant in groundwater. For this approach to be useful, however, the kinetic isotopic fractionations of O and Cl during perchlorate biodegradation must first be determined as a function of environmental variables such as temperature and bacterial species. A laboratory study was performed in which the O and Cl isotope ratios of perchlorate were monitored as a function of degradation by two separate bacterial strains (Azospira suillum JPLRND and Dechlorospirillum sp. FBR2) at both 10??C and 22??C with acetate as the electron donor. Perchlorate was completely reduced by both strains within 280 h at 22??C and 615 h at 10??C. Measured values of isotopic fractionation factors were ??18O = -36.6 to -29.0??? and ??37Cl = -14.5 to -11.5???, and these showed no apparent systematic variation with either temperature or bacterial strain. An experiment using 18O-enriched water (??18O = +198???) gave results indistinguishable from those observed in the isotopically normal water (??18O = -8.1???) used in the other experiments, indicating negligible isotope exchange between perchlorate and water during biodegradation. The fractionation factor ratio ??18O/??37Cl was nearly invariant in all experiments at 2.50 ?? 0.04. These data indicate that isotope ratio analysis will be useful for documenting perchlorate biodegradation in soils and groundwater. The establishment of a microbial fractionation factor ratio (??18O/??37Cl) also has significant implications for forensic studies. ?? 2007 American Chemical Society.

  9. A Reservoir of Natural Perchlorate in Unsaturated Zones of Arid and Semi-Arid Regions, Southwestern USA

    Science.gov (United States)

    Rao, B. A.; Stonestrom, D. A.; Anderson, T. A.; Orris, G. J.; Rajagapolan, S.; Sandvig, R. M.; Scanlon, B. R.; Walvoord, M. A.; Jackson, W.

    2006-12-01

    Natural perchlorate (ClO4-) is generally present in unsaturated zones of steppe-to-desert regions of the arid and semi-arid southwestern United States. The perchlorate is associated with atmospherically deposited chloride that has accumulated throughout the Holocene. To assess this natural reservoir, we analyzed unsaturated-zone profiles from ten sites across Nevada, New Mexico, Texas, and Utah for perchlorate and other anions. The sampled sites represent a wide range of precipitation (0.1 0.5 m yr-1), dominant vegetation, soil type, underlying geology, and include five distinct ecological regions: Chihuahuan, Mojave, and southern Great Basin deserts; Arizona-New Mexico semi-desert; and Texas High Plains dry steppe. Concentrations of perchlorate correlated closely with chloride and bromide. The perchlorate reservoir (up to 1 kg ha-1) is sufficiently large to impact groundwater when natural recharge during pluvial periods or induced recharge after conversion to agriculture flushes accumulated salts from the unsaturated zone. This little explored source can explain perchlorate in milk and other agricultural products far from anthropogenic contamination, and should be considered when evaluating overall exposure risk.

  10. Cesium-137 inventories in undisturbed areas in different regions of Brazil

    International Nuclear Information System (INIS)

    Cesium-137 is an anthropogenic radionuclide introduced in the environment in the early of 1960s to the end of 1970s. The Cesium-137 has very used to assess soil redistribution in the landscape because this is very tight in the fine soil particles and its movement in the landscape is due to soil redistribution. To use Cesium-137 to assess soil redistribution is need to known the Cesium-137 inventory in an area that not has experimented soil erosion neither soil deposition. So, this work present Cesium-137 inventories in undisturbed areas in different regions of Brazil, from South to Northeast of Brazil. The inventories in these areas represent the variational deposition of Cesium-137 in the whole national territory of Brazil. The inventories of Cesium-137 varied from 200 ± 15 Bq.m-2 for South region to 15 ± 2 Bq.m-2 for Northeast region. Moreover, was verified that the Cesium- 137 inventories depend on latitude and altitude of the area. (author)

  11. Peculiarities of presence of cesium-137 in soil at Azgir test site grounds

    International Nuclear Information System (INIS)

    The granulometric composition of soil and the distribution of cesium-137 by soil fractions at the Azgir test site was determined. The characterization of cesium-137 presence in the layer of the thickness of 1 cm of the surface soil was gave. (author)

  12. Velocity Distribution of Effective Atoms in a Small Optically Pumped Cesium Beam Frequency Standard

    Institute of Scientific and Technical Information of China (English)

    CHEN Jingbiao; WANG Fengzhi; YANG Donghai; WANG YiQiu

    2001-01-01

    In this paper, the velocity distribution of effective atoms in a small optically pumped cesium beam frequency standard has been achieved from the Fourier transforms of the experimentally recorded Ramsey patterns. The result fits well with the theoretical calculation. The second order Doppler shift correction of the small cesium atomic clock is obtained from the velocity distribution of effective atoms.

  13. Vacuum squeezed light for atomic memories at the D2 cesium line

    CERN Document Server

    Burks, Sidney; Giacobino, Elisabeth; Laurat, Julien; Ortalo, Jérémie; Jia, Xiaojun; Villa, Fabrizio; Chuimmo, Antonino

    2008-01-01

    We report the experimental generation of squeezed light at 852 nm, locked on the Cesium D2 line. 50% of noise reduction down to 50 kHz has been obtained with a doubly resonant optical parametric oscillator operating below threshold, using a periodically-polled KTP crystal. This light is directly utilizable with Cesium atomic ensembles for quantum networking applications

  14. Ionizing mechanisms in a cesium plasma irradiated with a ruby laser

    Science.gov (United States)

    Shimada, K.; Robinson, L. B.

    1975-01-01

    A cesium filled diode--laser plasmadynamic converter was built to investigate the feasibility of converting laser energy to electrical energy at large power levels. Experiments were performed with a pulsed ruby laser to determine the quantity of electrons and cesium ions generated per pulse of laser beam and to determine the output voltage. A current density as high as 200 amp/sq cm from a spot of approximately 1 sq mm area and an open circuit voltage as high as 1.5 volts were recorded. A qualitative theory was developed to explain these results. In the operation of the device, the laser beam evaporates some of the cesium and ionizes the cesium gas. A dense cesium plasma is formed to absorb further the laser energy. Results suggest that the simultaneous absorption of two ruby laser photons by the cesium atoms plays an important role in the initial ionization of cesium. Inverse bremsstrahlung absorption appears to be the dominant mechanism in subsequent processes. Recombinations of electrons and cesium ions appear to compete favorably with the simultaneous absorption of two photons.

  15. Sorption of iodine, chlorine, technetium and cesium in soil

    International Nuclear Information System (INIS)

    The safety assessment of final disposal of spent nuclear fuel will include an estimate for the behavior of waste nuclides in the biosphere. As a part of this estimate also the sorption of radioactive iodine, chlorine, technetium and cesium in soil is to be considered. The chemistry and the sorption of these radionuclides in soils are described in this literature survey. Behavior of I-129, Cl-36 and Tc-99 in the environment is of great interest because of their long half-lives and relatively high mobilities. The importance of Cs-135 arises from its high content in spent nuclear fuel and long physical half-life, even though it is considered relatively immobile in soil. Factors affecting the migration and sorption of radionuclides in soils can be divided into elemental and soil specific parameters. The most important elemental factor is the speciation of the element, which is influenced by the soil redox potential, pH and complex forming ligands. Soil micro-organisms can either serve as sorbents for radionuclides or affect their speciation by altering the prevailing soil redox conditions. Soil organic matter content and mineral properties have a marked influence on the retention of radionuclides. The sorption of anionic radionuclides such as I-, Cl- and TcO4 - is pronounced in the presence of organic matter. Clay minerals are known to bound cesium effectively. The effect of speciation of radioactive iodine, chlorine, technetium and cesium in soil is considered in this study, as well as the effect of soil micro-organisms, organic matter and mineral properties. (orig.)

  16. Cesium-137 inventory of the undisturbed soil areas in the Londrina Region, Parana, Brazil

    International Nuclear Information System (INIS)

    Cesium-137 is an artificial radionuclide introduced in the environment through the radioactive fallout of the superficial tests of nuclear weapons. The cesium-137 deposition occurred to middles of the 1980-decade and, due to the Chernobyl accident, great part of Europe had a additional fallout of cesium-137. The contaminations of this accident do not have reached Southern Hemisphere. Cesium-137 is an alkaline metal, high electropositive, that in contact with the soil is strongly adsorbed to the clay in the FES (Frayed Edge Sites) and RES (Regular Edge Sites) positions, and it movement by chemical processes in the soil is insignificant. Because of this, cesium-137 became a good soil marker, and its movement is related to the soil movement particles, so that the cesium-137 have been used in the study of the soil redistribution processes, as a tool of quantifying the rates of soil losses and gain. To use this methodology, it is necessary the knowledge of the reference inventory of cesium-137, that is given as function of the total concentration of cesium-137 deposited in an area by the radioactive fallout. If a sampling point presents less cesium-137 than the reference inventory, this point is considered a point with soil loss; otherwise, the point is considered a point with soil deposition. To evaluate the cesium-137 inventory in the Londrina region, four areas of the undisturbed soil were sampling in grid of 3x3, with a distance of 9 meters among the points. Of these four sampling areas, three areas were of native forest (labeled Mata1, Mata2 and Mata UEL), and one was a pasture area. Cesium-137 inventory was 223 ± 41 Bq m-2, 240 ± 65 Bq m-2 and 305 ± 36 Bq m-2 for Mata UEL, Mata1 and Mata2, respectively, and of 211 ± 28 Bq m-2 for the native pasture. Considering the deviation in each value, it is not possible to conclude that there are differences among the values of cesium-137 inventory, so that the average reference inventory of cesium-137 for the Londrina

  17. Rational Design of Cesium-Selective Ionophores and Chemosensors: Dihydrocalix[4]arene Crown-6 Ethers

    Energy Technology Data Exchange (ETDEWEB)

    Sachleben, Richard A.; Bryan, Jeffrey C.; Brown, Gilbert M.; Engle, Nancy L.; Haverlock, Tamara J.; Hay, Benjamin P.; Urvoas, Agathe; Moyer, Bruce A.

    2003-12-15

    Molecular mechanics calculations performed on calix[4]arene crown-6 ethers predict that the 1,3-dihydro derivatives will exhibit greater complementarity for potassium and cesium ions than the parent 1,3-dialkoxy calix crowns. The X-ray crystal structures of 1,3-alt bis-octyloxycalix[4]arene benzocrown-6 ether, dihydrocalix[4]arene benzocrown-6 ether, and the cesium nitrate complex of dihydrocalix[4]arene benzocrown-6 ether were determined. The cesium complex structure corresponds closely to the structure predicted by molecular mechanics. The dihydrocalix[4]arene crown-6 ethers exhibit enhanced cesium selectivity in the extraction of alkali metal salts and provide a platform for a highly sensitive and selective cesium chemosensor.

  18. [Variation in amount of radioactive cesium before and after cooking dry shiitake and beef].

    Science.gov (United States)

    Nabeshi, Hiromi; Tsutsumi, Tomoaki; Hachisuka, Akiko; Matsuda, Rieko

    2013-01-01

    We investigated the change of radioactive cesium content in food due to cooking in order to estimate the internal radiation exposure due to from radioactive materials in food. Our results revealed that soaking dry shiitake in water decreased the radioactive cesium content by about 50%, compared with that present in uncooked shiitake. Radioactive cesium in beef was decreased by about 10%, 12%, 60-65% and 80% by grilling, frying, boiling and stewing, respectively, compared to uncooked beef. For cooked beef, the decrease in the ratio of radioactive cesium was significantly different among the types of cooking. The decrease ratio of radioactive cesium in boiled and stewed beef was 8 times higher than that in grilled and fried beef.

  19. Tetranitroacetimidic acid: a high oxygen oxidizer and potential replacement for ammonium perchlorate.

    Science.gov (United States)

    Vo, Thao T; Parrish, Damon A; Shreeve, Jean'ne M

    2014-08-27

    Considerable work has been focused on developing replacements for ammonium perchlorate (AP), a primary choice for solid rocket and missile propellants, due to environmental concerns resulting from the release of perchlorate into groundwater systems [corrected]. Additionally, the generation of hydrochloric acid contributes to high concentrations of acid rain and to ozone layer depletion. En route to synthesizing salts that contain cationic FOX-7, a novel, high oxygen-containing oxidizer, tetranitroacetimidic acid (TNAA), has been synthesized and fully characterized. The properties of TNAA were found to be exceptional, with a calculated specific impulse exceeding that of AP, leading to its high potential as a replacement for AP. TNAA can be synthesized easily in a one-step process by the nitration of FOX-7 in high yield (>93%). The synthesis, properties, and chemical reactivity of TNAA have been examined.

  20. The processing, properties and use of the pyrotechnic mixture titanium subhydride/potassium perchlorate

    Energy Technology Data Exchange (ETDEWEB)

    Massis, T.M.

    1996-07-01

    Development of this pyrotechnic occurred because of the need for a static insensitive material to meet personnel safety requirements and related system safety issues in nuclear weapon energetic material component designs. Ti subhydride materials are made by the thermal dehydrding of commercial Ti hydride powder to the desired equivalent hydrogen composition in the Ti lattice. These Ti subhydrides, when blended with K perchlorate, meet the static insensitivity requirement of not being initiated from an equivalent human body electrostatic discharge. Individual material and blend qualification requirements provide a reproducible material from lot to lot. These pyrotechnic formulations meet the high reliability requirements (0.9995) for initiation and performance parameters and have the necessary stability and compatibility to meet long lived requirements of more than 25 years. Various experiences and problems are also discussed that have led to a mature technology for Ti subhydride/K perchlorate during its use in energetic material component designs.

  1. Sensitive Detection of Cold Cesium Molecules by Radiative Feshbach Spectroscopy

    OpenAIRE

    Chin, Cheng; Kerman, Andrew J.; Vuletić, Vladan; Chu, Steven

    2002-01-01

    We observe the dynamic formation of $Cs_2$ molecules near Feshbach resonances in a cold sample of atomic cesium using an external probe beam. This method is 300 times more sensitive than previous atomic collision rate methods, and allows us to detect more than 20 weakly-coupled molecular states, with collisional formation cross sections as small as $\\sigma =3\\times 10^{-16}$cm$^2$. We propose a model to describe the atom-molecule coupling, and estimate that more than $2 \\times 10^5$ $Cs_2$ mo...

  2. Characterizing optical dipole trap via fluorescence of trapped cesium atoms

    Institute of Scientific and Technical Information of China (English)

    LIU; Tao; GENG; Tao; YAN; Shubin; LI; Gang; ZHANG; Jing; WANG; Junmin; PENG; Kunchi; ZHANG; Tiancai

    2006-01-01

    Optical dipole trap (ODT) is becoming an important tool of manipulating neutral atoms. In this paper ODT is realized with a far-off resonant laser beam strongly focused in the magneto-optical trap (MOT) of cesium atoms. The light shift is measured by simply monitoring the fluorescence of the atoms in the magneto-optical trap and the optical dipole trap simultaneously. The advantages of our experimental scheme are discussed, and the effect of the beam waist and power on the potential of dipole trap as well as heating rate is analyzed.

  3. Cesium fallout in Norway after the Chernobyl accident

    International Nuclear Information System (INIS)

    Results of country-wide measurements of 137Cs and 134 Cs in soil samples in Norway after the Chernobyl accident are reported. The results clearly demonstrates that municipalities in the central part of southern Norway, Troendelag and the southern part of Nordland, have been rather heavily contaminated. The total fallout of 137Cs and 134Cs from the Chernobyl accident in Norway is estimated to 2300 TBq and 1200 TBq, respectively. This is approximately 6% of the cesium activity released from the reactor

  4. The Investigation of Perchlorate/Iron Phase Mixtures as A Possible Source of Oxygen Detected by the Sample Analysis at Mars (SAM) Instrument in Gale Crater, Mars

    Science.gov (United States)

    Sutter, B.; Heil, E.; Morris, R. V.; Archer, P. D.; Ming, D. W.; Niles, P. B.; Eigenbrode, J. L.; Franz, H.; Freissinet C.; Glavin, D. P.; McAdam, A. C.; Mahaffy, P.; Martin-Torres, F. Javier; Navarro-Gonzalez, R.; Paz-Zorzano, Maria; Stern, J. C.; McKay, C. P.

    2015-01-01

    The Sample Analysis at Mars (SAM) instrument onboard the Curiosity rover detected O2 and HCl gas releases from the Rocknest (RN) eolian bedform and the John Klein (JK) and Cumberland (CB) drill hole materials in Gale Crater. Chlorinated hydrocarbons have also been detected by the SAM quadrupole mass spectrometer (QMS) and gas chromatography/mass spectrometer (GCMS). These detections along with the detection of perchlorate (ClO4-) by the Mars Phoenix Lander's Wet Chemistry Laboratory (WCL) suggesting perchlorate is a possible candidate for evolved O2 and chlorine species. Laboratory thermal analysis of individual per-chlorates has yet to provide an unequivocal temperature match to the SAM O2 and HCl release data. These detections along with the detection of perchlorate (ClO4-) by the Mars Phoenix Lander's Wet Chemistry Laboratory suggested perchlorate is a possible candidate for evolved O2 and chlorine species. Laboratory thermal analysis of pure perchlorates has yet to provide an unequivocal temperature match to the SAM O2 and HCl release data. Analog laboratory analysis of iron mineralogy detected in Gale materials that was physically mixed with Ca- and Mg-perchlorate has been shown to catalyze lower O2 release temperatures and approach some SAM O2 release data. Instead of physical mixtures used in previous work, the work presented here utilized perchlorate solutions added to Fe phases. This technique allowed for perchlorate to come in closer contact with the Fe-phase and may more closely mimic Mars conditions where humidity can increase enough to cause deliquescence of the highly hygroscopic perchlorate phases. The objective of this work is to: 1) Utilize a laboratory SAM analog instrument to evaluate the O2 release temperatures from Mg- and Ca-perchlorates solutions applied to Fephases detetected in Gale Crate; and 2) Determine if perchlorate solutions can provide improved matches with the SAM O2 temperature release profiles.

  5. Composition change of uranium perchlorates with organic ligands upon mechanochemical activation of exchange processes

    Science.gov (United States)

    Zazhogin, A. P.; Zazhogin, A. A.; Komyak, A. I.; Umreiko, D. S.

    2008-03-01

    Results of studies on the effect of mechanochemical activation of ligand exchange processes in uranyl perchlorate-dimethylsulfoxide are presented. Spectroscopic data show that mechanical activation of the exchange process in this system results in the replacement of H2O in the first coordination sphere of uranyl UO{2/2+} by DMSO to form nanocrystals with a defined ligand sphere. Possible factors governing the noted features are considered.

  6. Sweet and Sour: Attenuating Sulfidogenesis in an Advective Flow Column System with Perchlorate or Nitrate Treatment

    Science.gov (United States)

    Engelbrektson, A. L.; Hubbard, C. G.; Piceno, Y.; Boussina, A.; Jin, Y.; Dubinsky, E. A.; Tom, L.; Hu, P.; Conrad, M. E.; Anderson, G. L.; Coates, J. D.

    2013-12-01

    Hydrogen sulfide (H2S) biogenesis in oil reservoirs is a primary cause of souring and of associated costs in reservoir and pipeline maintenance. In addition to the corrosive effects of the H2S itself, abiotic and biological oxidation also generates sulfuric acid, further degrading metallic surfaces. Amending these environments with perchlorate (ClO4-) resolves these problems by inhibition of biological sulfate reduction and re-oxidation of H2S to elemental sulfur by dissimilatory (per)chlorate reducing bacteria (DPRB). Triplicate flow through columns packed with San Francisco bay sediment were flushed with bay water ([SO4=] = 25-30 mM) containing yeast extract with 50 mM inhibitor concentrations (NO3-or ClO4-) decreasing to 25 mM and finally 12.5 mM. Influent and effluent geochemistry was monitored and DNA was prepared from the sediment bed for microbial community analysis. Souring was reversed by both treatments (at 50 mM) compared to the control columns that had no ion addition. Nitrate began to re-sour when treatment concentration was decreased to 25 mM but treatment had to be decreased to 12.5 mM before the perchlorate treated columns began to re-sour. However, the treated columns re-soured to a lesser extent than the control columns. Phylochip microbial community analyses indicated microbial community shifts and phylogenetic clustering by treatment. Isotopic analysis of sulfate showed trends that broadly agreed with the geochemistry but also suggested further sulfur cycling was occurring. This study indicates that perchlorate shows great promise as an inhibitor of sulfidogenesis in natural communities and provides insight into which organisms are involved in this process.

  7. Electrochromic iridium oxide films: Compatibility with propionic acid, potassium hydroxide, and lithium perchlorate in propylene carbonate

    OpenAIRE

    Wen, Rui-Tao; Niklasson, Gunnar A.; Granqvist, Claes G.

    2013-01-01

    Porous thin films of It oxide were prepared by reactive dc magnetron sputtering onto unheated substrates. The crystallite size was similar to 5 nm, and a small amount of unoxidized Ir was present. The electrochromic performance was studied by optical transmittance measurements and cyclic voltammetry applied to films in aqueous and non-aqueous electrolytes, specifically being 1 M propionic acid, 1 M potassium hydroxide (KOH), and 1 M lithium perchlorate in propylene carbonate (Li-PC). Cyclic v...

  8. Disproportionation of plutonium IV in concentrated solutions of plutonium in perchloric acid

    International Nuclear Information System (INIS)

    This work was carried out to study the dependence of the PuIV disproportionation reaction in perchloric acid solution on the plutonium concentration up to 20 g/l. Solutions of such high plutonium concentration have not previously been studied. It was found that the bimolecular rate constant and the equilibrium constant of the disproportionation reaction were not appreciably different from their values at lower concentrations. (author)

  9. The ionic product of water in highly concentrated sodium perchlorate solutions.

    Science.gov (United States)

    Turonek, M L; Hefter, G T; May, P M

    1998-03-01

    The ionic product of water, pK(w)=-log[H(+)][OH(-)], has been determined in aqueous solutions of sodium perchlorate over the concentration range of 1.0-8.0 M at 25 degrees C from high-precision potentiometric titrations carried out in cells with liquid junction using both glass and hydrogen electrodes. The glass electrode results are systematically lower probably as a result of interference by Na(+) ions.

  10. The use of chlorate, nitrate, and perchlorate to promote crude oil mineralization in salt marsh sediments.

    Science.gov (United States)

    Brundrett, Maeghan; Horita, Juske; Anderson, Todd; Pardue, John; Reible, Danny; Jackson, W Andrew

    2015-10-01

    Due to the high volume of crude oil released by the Deepwater Horizon oil spill, the salt marshes along the gulf coast were contaminated with crude oil. Biodegradation of crude oil in salt marshes is primarily limited by oxygen availability due to the high organic carbon content of the soil, high flux rate of S(2-), and saturated conditions. Chlorate, nitrate, and perchlorate were evaluated for use as electron acceptors in comparison to oxygen by comparing oil transformation and mineralization in mesocosms consisting of oiled salt marsh sediment from an area impacted by the BP Horizon oil spill. Mineralization rates were determined by measuring CO2 production and δ (13)C of the produced CO2 and compared to transformation evaluated by measuring the alkane/hopane ratios over a 4-month period. Total alkane/hopane ratios decreased (~55-70 %) for all treatments in the following relative order: aerated ≈ chlorate > nitrate > perchlorate. Total CO2 produced was similar between treatments ranging from 550-700 mg CO2-C. The δ (13)C-CO2 values generally ranged between the indigenous carbon and oil values (-17 and -27‰, respectively). Oil mineralization was greatest for the aerated treatments and least for the perchlorate amended. Our results indicate that chlorate has a similar potential as oxygen to support oil mineralization in contaminated salt marshes, but nitrate and perchlorate were less effective. The use of chlorate as a means to promote oil mineralization in situ may be a promising means to remediate contaminated salt marshes while preventing unwanted secondary impacts related to nutrient management as in the case of nitrate amendments. PMID:25854211

  11. Widespread occurrence of perchlorate in water, foodstuffs and human urine collected from Kuwait and its contribution to human exposure.

    Science.gov (United States)

    Alomirah, Husam F; Al-Zenki, Sameer F; Alaswad, Marivi C; Alruwaih, Noor A; Wu, Qian; Kannan, Kurunthachalam

    2016-06-01

    Perchlorate is a thyroid hormone-disrupting compound and is reported to occur widely in the environment. Little is known on human exposure to perchlorate in Kuwait. In this study, 218 water samples, 618 commonly consumed foodstuffs and 532 urine samples collected from Kuwait were analysed to assess the exposure of the Kuwaiti population to perchlorate. For the estimation of daily intake of perchlorate, food consumption rates were obtained from the National Nutrition Survey in the State of Kuwait (NNSSK). The results showed that leafy vegetables accounted for a major share of perchlorate exposure among the Kuwaiti population at 0.062 µg kg(-)(1) bw day(-)(1) (36.2%), followed by fruits at 0.026 µg kg(-)(1) bw day(-)(1) (15.3%) and non-leafy vegetables at 0.017 µg kg(-)(1) bw day(-)(1) (10.1%). The urinary perchlorate geometric mean (GM) concentrations ranged from 8.51 to 17.1 µg l(-)(1) for the five age groups, which were higher than those reported in other countries. The estimated urinary perchlorate exposure for the Kuwaiti general population was 0.42 µg kg(-)(1) bw day(-)(1), which was higher than that reported for the United States. The dietary intake of perchlorate for the Kuwaiti population ranged from 0.14 to 0.67 µg kg(-)(1) bw day(-)(1) for the five age groups, with a mean total daily intake of 0.17 µg kg(-)(1) bw day(-)(1) for the general population. The highest estimated dietary mean daily intake of perchlorate (0.67 µg kg(-)(1) bw day(-)(1)) was found for children at 3-5 years. The estimated dietary perchlorate exposure in Kuwait is higher than the recommended mean reference dose (RfD) but lower than that of provisional maximum tolerable daily intake (PMTDI) set by the Joint FAO/WHO Expert Committee on Food Additives (JECFA). PMID:27248576

  12. Temporal and spatial variation of perchlorate in streambed sediments: results from in-situ dialysis samplers

    International Nuclear Information System (INIS)

    The fate of perchlorate (ClO4-) in streambed sediments is becoming a concern due to the increasing number of groundwater and surface water contamination sites in the United States. Dialysis samplers were deployed at three sites over a period of 1 year to determine the vertical distribution of ClO4-in sediment pore water. Results indicated that the spatial and temporal ClO4-penetration into sediments could be affected by numerous factors, such as temperature, microbial degradation, ClO4-surface water concentration, and sediment physico-geological properties. In general, maximum ClO4-penetration into sediments at the studied sites was 30 cm below the sediment-water surface. The vertical sequential depletion of electron acceptors in sediments suggested that microbial reduction was responsible for ClO4-depletion in stream sediments. Biodegradation of ClO4-occurred over a seasonally variable active depth zone of 1-10 cm. Results implied that there was a rapid natural attenuation potential of perchlorate in saturated near-surface sediments. -Perchlorate may be rapidly attenuated in saturated near-surface sediments

  13. Research Advances: Perchlorate in Dairy and Breast Milk Samples; NO Glow on Mars; Physical Chemistry to the Rescue: Differentiating Nicotinic and Cholinergic Agonists

    Science.gov (United States)

    King, Angela G.

    2005-07-01

    Perchlorate levels in milk suggest widespread presence of the chemical. NO emissions indicate circulation in Martian atmosphere. Modeling reveals subtle differences in drug membrane receptor interactions.

  14. Morphological and electrical properties of zirconium vanadate doped with cesium

    Directory of Open Access Journals (Sweden)

    Marwa F. Elkady

    2014-09-01

    Full Text Available Cesium doped zirconium vanadate ZrV2O7 with different Cs dopant content (Cs/Zr varied from 0 to 0.5 in weight ratio were fabricated by hydrothermal technique at 120 °C for 60 min. The synthesized materials are thermally treated using microwave technique. The structural and morphological properties of the synthesized materials and thermally treated samples were investigated using XRD and SEM respectively. It was evident that all synthesized specimens have cubic phase structural without any extra phase but after heat treatment Orthorhombic phase appear with doped samples. However, the morphological structure of the doped synthesized materials has transferred from nanoparticles into rods aspect with heat treatment for the different dopant ratio. Moreover, the electrical properties of both the synthesized and thermally treated materials are studied by AC impedance measurements. The results indicated that the ionic conductivity of Cs-doped ZrV2O7 materials decreased by increasing the dopant ratio while that thermally treated samples the ionic conductivity increase by increasing the dopant ratio. Finally, the concentration of cesium dopants is found to play crucial role in tuning the morphology and electrical properties of nanostructures.

  15. Transportable cesium irradiator (TPCI): Final safety analysis report: Revision 1

    International Nuclear Information System (INIS)

    This Final Safety Analysis Report describes the Transportable Cesium Irradiator (TPCI) and assesses the hazards associated with its operation. The TPCI consists of a mobile, lead-shielded, irradiation unit with support equipment mounted within an enclosed trailer. The irradiation unit has two basic compartments; a source chamber sized to mate with the transportation cask which houses the source capsules, and an irradiation chamber formed as a large shielded cylinder (drum) with a window. The irradiation chamber is mounted on a large diameter support bearing. As this chamber is rotated its window moves from the product access door, where produce is inserted or extracted, to a position in line with a similar window in the source chamber. When the windows are aligned the produce is irradiated, while the back wall of the irradiation chamber shields the product access door. The TPCI is designed to be transported throughout the continental United States. The transportation cask containing the cesium source capsules is transported separately from the irradiation unit and is installed when the TPCI unit has been readied for operation at a particular site. The transportation cask is a separate unit and is documented in a separate FSAR

  16. Kelvin probe studies of cesium telluride photocathode for AWA photoinjector

    Energy Technology Data Exchange (ETDEWEB)

    Wisniewski, Eric E., E-mail: ewisniew@anl.gov [High Energy Physics Division, Argonne National Laboratory, 9700 S. Cass, Lemont, IL 60439 (United States); Physics Department, Illinois Institute of Technology, 3300 South Federal Street, Chicago, IL 60616 (United States); Velazquez, Daniel [High Energy Physics Division, Argonne National Laboratory, 9700 S. Cass, Lemont, IL 60439 (United States); Physics Department, Illinois Institute of Technology, 3300 South Federal Street, Chicago, IL 60616 (United States); Yusof, Zikri, E-mail: zyusof@hawk.iit.edu [High Energy Physics Division, Argonne National Laboratory, 9700 S. Cass, Lemont, IL 60439 (United States); Physics Department, Illinois Institute of Technology, 3300 South Federal Street, Chicago, IL 60616 (United States); Spentzouris, Linda; Terry, Jeff [Physics Department, Illinois Institute of Technology, 3300 South Federal Street, Chicago, IL 60616 (United States); Sarkar, Tapash J. [Rice University, 6100 Main, Houston, TX 77005 (United States); Harkay, Katherine [Accelerator Science Division, Argonne National Laboratory, 9700 S. Cass, Lemont, IL 60439 (United States)

    2013-05-21

    Cesium telluride is an important photocathode as an electron source for particle accelerators. It has a relatively high quantum efficiency (>1%), is sufficiently robust in a photoinjector, and has a long lifetime. This photocathode is grown in-house for a new Argonne Wakefield Accelerator (AWA) beamline to produce high charge per bunch (≈50nC) in a long bunch train. Here, we present a study of the work function of cesium telluride photocathode using the Kelvin probe technique. The study includes an investigation of the correlation between the quantum efficiency and the work function, the effect of photocathode aging, the effect of UV exposure on the work function, and the evolution of the work function during and after photocathode rejuvenation via heating. -- Highlights: ► The correlation between Quantum Efficiency (QE) and work function. ► How QE and work function evolve together. ► Rejuvenation of the photocathode via heating and the effect on work function. ► The effects on the work function due to exposure to UV light.

  17. Structure and bonding in crystalline cesium uranyl tetrachloride under pressure.

    Science.gov (United States)

    Osman, Hussien H; Pertierra, Pilar; Salvadó, Miguel A; Izquierdo-Ruiz, F; Recio, J M

    2016-07-21

    A thorough investigation of pressure effects on the structural properties of crystalline cesium uranyl chloride was performed by means of first-principles calculations within the density functional theory framework. Total energies, equilibrium geometries and vibrational frequencies were computed at selected pressures up to 50 GPa. Zero pressure results present good agreement with available experimental and theoretical data. Our calculated equation of state parameters reveal that Cs2UO2Cl4 is a high compressible material, similar to other ionic compounds with cesium cations, and displays a structural anisotropic behavior guided by the uranyl moiety. An unexpected variation of the U-O bond length, dUO, is detected as pressure is applied. It leads to a dUO-stretching frequency relationship that cannot be described by the traditional Badger's rule. Interestingly enough, it can be explained in terms of a change in the main factor controlling dUO. At low pressure, the charge transferred to the uranyl cation induces an increase of the bond length and a red shift of the stretching frequencies, whereas it is the mechanical effect of the applied pressure above 10 GPa that is the dominant factor that leads to a shortening of dUO and a blue shift of the stretching frequencies. PMID:27340008

  18. Spectrally selective optical pumping in Doppler-broadened cesium atoms

    Institute of Scientific and Technical Information of China (English)

    Zhang Jun-Hai; Zeng Xian-Jin; Li Qing-Meng; Huang Qiang; Sun Wei-Min

    2013-01-01

    The D1 line spectrally selective pumping process in Doppler-broadened cesium is analyzed by solving the optical Bloch equations.The process,described by a three-level model with the A scheme,shows that the saturation intensity of broadened atoms is three orders of magnitude larger than that of resting atoms.The |Fg =3> → |Fe-4> resonance pumping can result in the ground state |Fg =4,mF =4> sublevel having a maximum population of 0.157 and the population difference would be about 0.01 in two adjacent magnetic sublevels of the hyperfine (HF) state Fg =4.To enhance the anisotropy in the ground state,we suggest employing dichromatic optical HF pumping by adding a laser to excite D1 line |Fg =4> → |Fe =3>transition,in which the cesium magnetometer sensitivity increases by half a magnitude and is unaffected by the nonlinear Zeeman effect even in Earth's average magnetic field.

  19. Structure and bonding in crystalline cesium uranyl tetrachloride under pressure.

    Science.gov (United States)

    Osman, Hussien H; Pertierra, Pilar; Salvadó, Miguel A; Izquierdo-Ruiz, F; Recio, J M

    2016-07-21

    A thorough investigation of pressure effects on the structural properties of crystalline cesium uranyl chloride was performed by means of first-principles calculations within the density functional theory framework. Total energies, equilibrium geometries and vibrational frequencies were computed at selected pressures up to 50 GPa. Zero pressure results present good agreement with available experimental and theoretical data. Our calculated equation of state parameters reveal that Cs2UO2Cl4 is a high compressible material, similar to other ionic compounds with cesium cations, and displays a structural anisotropic behavior guided by the uranyl moiety. An unexpected variation of the U-O bond length, dUO, is detected as pressure is applied. It leads to a dUO-stretching frequency relationship that cannot be described by the traditional Badger's rule. Interestingly enough, it can be explained in terms of a change in the main factor controlling dUO. At low pressure, the charge transferred to the uranyl cation induces an increase of the bond length and a red shift of the stretching frequencies, whereas it is the mechanical effect of the applied pressure above 10 GPa that is the dominant factor that leads to a shortening of dUO and a blue shift of the stretching frequencies.

  20. A study of strontium and cesium sorption on granite

    International Nuclear Information System (INIS)

    The diffusion and sorption of cesium and strontium in crushed granite particles is discussed. Sorption experiments have been performed with one granite from Finnsjoen outside Forsmark on the east coast of Sweden and one granite from the Stripa mine in central Sweden. Granite samples have been crushed and screened, and six different particle size fractions from 0.10-0.12 mm to 4-5 mm of each rock have been used in the experiments. The initial concentrations of inactive cesium and strontium were 10-15 ppm. The experimental data indicate that the amount of sorption is dependent not only on the mass of granite particles, but also to some extent on the size of the particles. An attempt has been made to distinguish between sorption on external surfaces and inner surfaces. The amount of external surface adsorption was found to vary from 15-40 % of the total adsorption capacity for the particle size fraction 0.10-0.12 mm to a few percent or less for the largest particles used. (Auth.)

  1. Diffusion of strontium, technetium, iodine and cesium in granitic rock

    International Nuclear Information System (INIS)

    The migration of strontium, technetium, iodine and cesium in granitic rock has been studied. Rock samples were taken from drilling cores in granitic and granodioritic rock, and small (2x2x2 cm) rock tablets from the drilling cores were exposed to a groundwater solution containing one of the studied elements at trace levels. The concentration of the element versus penetration depth in the rock tablet was measured radiometrically. The sorption on the mineral faces and the diffusion into the rock were studied by an autoradiographic technique. The cationic strontium and cesium have apparent diffusivities of 10-13 - 10-14 m2/s. The migration is confined to microfissures or filled fractures containing e.g., calcite, epidote or chlorite or in veins with high capacity minerals (e.g. biotite). The anionic iodine and technetium have apparent diffusivities of about 10-14 m2/s. These species migrate along mineral boundaries and in open fractures and to a minor extent in high capacity mineral veins. (orig.)

  2. Studies on cesium sorption in hydrous zirconium and titanium oxides

    International Nuclear Information System (INIS)

    Significant quantities of 137Cs (T1/2 = 30.1 y) and 90Sr (T1/2 = 28.5 y) are produced as fission products in nuclear reactors. These long-lived gamma-emitting radionuclides, regarded as a waste few decades ago, are being termed now as valuables owing to the upsurge in the utilization of these radioisotopes in the area of medicine, food irradiation, and sewage treatment technologies in recent years. For long-term waste management it is necessary to minimize the volume and toxicity of the waste. Selective recovery and utilization of these radionuclides from the waste is the concept of growing interest to many researchers. Inorganic sorbents are proven candidates for the separation and recovery of cesium and strontium from aqueous waste streams. They are chemically durable and stable against ionizing radiation. In addition, these materials can be converted into unleachable ceramic form for final disposal. Hydrous metal oxides belong to a particular class of inorganic ion exchangers extensively investigated for various applications in nuclear waste treatment. The present study deals with the preparation of hydrous zirconium and titanium oxide and the studies aimed at separation of cesium from aqueous wastes

  3. Inhibition of microbial sulfate reduction in a flow-through column system by (per)chlorate treatment.

    Science.gov (United States)

    Engelbrektson, Anna; Hubbard, Christopher G; Tom, Lauren M; Boussina, Aaron; Jin, Yong T; Wong, Hayden; Piceno, Yvette M; Carlson, Hans K; Conrad, Mark E; Anderson, Gary; Coates, John D

    2014-01-01

    Microbial sulfate reduction is a primary cause of oil reservoir souring. Here we show that amendment with chlorate or perchlorate [collectively (per)chlorate] potentially resolves this issue. Triplicate packed columns inoculated with marine sediment were flushed with coastal water amended with yeast extract and one of nitrate, chlorate, or perchlorate. Results showed that although sulfide production was dramatically reduced by all treatments, effluent sulfide was observed in the nitrate (10 mM) treatment after an initial inhibition period. In contrast, no effluent sulfide was observed with (per)chlorate (10 mM). Microbial community analyses indicated temporal community shifts and phylogenetic clustering by treatment. Nitrate addition stimulated Xanthomonadaceae and Rhizobiaceae growth, supporting their role in nitrate metabolism. (Per)chlorate showed distinct effects on microbial community structure compared with nitrate and resulted in a general suppression of the community relative to the untreated control combined with a significant decrease in sulfate reducing species abundance indicating specific toxicity. Furthermore, chlorate stimulated Pseudomonadaceae and Pseudoalteromonadaceae, members of which are known chlorate respirers, suggesting that chlorate may also control sulfidogenesis by biocompetitive exclusion of sulfate-reduction. Perchlorate addition stimulated Desulfobulbaceae and Desulfomonadaceae, which contain sulfide oxidizing and elemental sulfur-reducing species respectively, suggesting that effluent sulfide concentrations may be controlled through sulfur redox cycling in addition to toxicity and biocompetitive exclusion. Sulfur isotope analyses further support sulfur cycling in the columns, even when sulfide is not detected. This study indicates that (per)chlorate show great promise as inhibitors of sulfidogenesis in natural communities and provides insight into which organisms and respiratory processes are involved. PMID:25071731

  4. Equilibrium, kinetic and thermodynamic study of cesium adsorption onto nanocrystalline mordenite from high-salt solution.

    Science.gov (United States)

    Lee, Keun-Young; Park, Minsung; Kim, Jimin; Oh, Maengkyo; Lee, Eil-Hee; Kim, Kwang-Wook; Chung, Dong-Yong; Moon, Jei-Kwon

    2016-05-01

    In this study, the equilibrium, kinetics and thermodynamics of cesium adsorption by nanocrystalline mordenite were investigated under cesium contamination with high-salt solution, simulating the case of an operation and decommissioning of nuclear facilities or an accident during the processes. The adsorption rate constants were determined using a pseudo second-order kinetic model. The kinetic results strongly demonstrated that the cesium adsorption rate of nano mordenite is extremely fast, even in a high-salt solution, and much faster than that of micro mordenite. In the equilibrium study, the Langmuir isotherm model fit the cesium adsorption data of nano mordenite better than the Freundlich model, which suggests that cesium adsorption onto nano mordenite is a monolayer homogeneous adsorption process. The obtained thermodynamic parameters indicated that the adsorption involved a very stable chemical reaction. In particular, the combination of rapid particle dispersion and rapid cesium adsorption of the nano mordenite in the solution resulted in a rapid and effective process for cesium removal without stirring, which may offer great advantages for low energy consumption and simple operation. PMID:26683820

  5. Rapid measurement of perchlorate in polar ice cores down to sub-ng L(-1) levels without pre-concentration.

    Science.gov (United States)

    Peterson, Kari; Cole-Dai, Jihong; Brandis, Derek; Cox, Thomas; Splett, Scott

    2015-10-01

    An ion chromatography-electrospray ionization-tandem mass spectrometry (IC-ESI-MS/MS) method has been developed for rapid and accurate measurement of perchlorate in polar snow and ice core samples in which perchlorate concentrations are expected to be as low as 0.1 ng L(-1). Separation of perchlorate from major inorganic species in snow is achieved with an ion chromatography system interfaced to an AB SCIEX triple quadrupole mass spectrometer operating in multiple reaction monitoring mode. Under optimized conditions, the limit of detection and lower limit of quantification without pre-concentration have been determined to be 0.1 and 0.3 ng L(-1), respectively, with a linear dynamic range of 0.3-10.0 ng L(-1) in routine measurement. These represent improvements over previously reported methods using similar analytical techniques. The improved method allows fast, accurate, and reproducible perchlorate quantification down to the sub-ng L(-1) level and will facilitate perchlorate measurement in the study of natural perchlorate production with polar ice cores in which perchlorate concentrations are anticipated to vary in the low and sub-ng L(-1) range. Initial measurements of perchlorate in ice core samples from central Greenland show that typical perchlorate concentrations in snow dated prior to the Industrial Revolution are about 0.8 ng L(-1), while perchlorate concentrations are significantly higher in recent (post-1980) snow, suggesting that anthropogenic sources are a significant contributor to perchlorate in the current environment. PMID:26297465

  6. Preliminary Evaluation of Cesium Distribution for Wet Sieving Process Planned for Soil Decontamination in Japan - 13104

    Energy Technology Data Exchange (ETDEWEB)

    Enokida, Y.; Tanada, Y.; Hirabayashi, D. [Graduate School of Engineering, 1 Furo-cho Nagoya-shi, Aichi-ken, 4648603 (Japan); Sawada, K. [EcoTopia Science Institute, Nagoya University, 1 Furo-cho Nagoya-shi, Aichi-ken, 4648603 (Japan)

    2013-07-01

    For the purpose of decontaminating radioactive cesium from a huge amount of soil, which has been estimated to be 1.2x10{sup 8} m{sup 3} by excavating to a 5-cm depth from the surface of Fukushima Prefecture where a severe nuclear accident occurred at TEPCO's power generating site and has emitted a significant amount of radioactive materials, mainly radioactive cesium, a wet sieving process was selected as one of effective methods available in Japan. Some private companies have demonstrated this process for soil treatment in the Fukushima area by testing at their plants. The results were very promising, and a full-fledged application is expected to follow. In the present study, we spiked several aqueous samples containing soil collected from an industrial wet sieving plant located near our university for the recycling of construction wastes with non-radioactive cesium hydroxide. The present study provides scientific data concerning the effectiveness in volume reduction of the contaminated soil by a wet sieving process as well as the cesium distribution between the liquid phase and clay minerals for each sub-process of the full-scale one, but a simulating plant equipped with a process of coagulating sedimentation and operational safety fundamentals for the plant. Especially for the latter aspect, the study showed that clay minerals of submicron size strongly bind a high content of cesium, which was only slightly removed by coagulation with natural sedimentation (1 G) nor centrifugal sedimentation (3,700 G) and some of the cesium may be transferred to the effluent or recycled water. By applying ultracentrifugation (257,000 G), most of submicron clay minerals containing cesium was removed, and the cesium amount which might be transferred to the effluent or recycled water, could be reduced to less than 2.3 % of the original design by the addition of a cesium barrier consisting of ultracentrifugation or a hollow fiber membrane. (authors)

  7. Hydrogen and Cesium Monitor for H- Magnetron Sources

    Energy Technology Data Exchange (ETDEWEB)

    Tan, Cheng-Yang [Fermilab; Bollinger, Dan [Fermilab; Schupbach, Brian [Fermilab; Seiya, Kiyomi [Fermilab

    2014-07-01

    The relative concentration of cesium to hydrogen in the plasma of a H- magnetron source is an important parameter for reliable operations. If there is too much cesium, the surfaces of the source become contaminated with it and sparking occurs. If there is too little cesium then the plasma cannot be sustained. In order to monitor these two elements, a spectrometer has been built and installed on a test and operating source that looks at the plasma. It is hypothesized that the concentration of each element in the plasma is proportional to the intensity of their spectral lines.

  8. Effect of Rare Earth Elements on Exchange Performances of Cesium Ion-Sieve

    Institute of Scientific and Technical Information of China (English)

    张惠源; 王榕树; 林灿生; 张先业

    2003-01-01

    The exchange performances and the distribution coefficient of Cesium Ion-Sieve (Cs-IS) for cesium and for some rare earth elements were compared. In particular, the effects of neodymium on the cesium ion exchange and the Cs+ selectivity variation on Cs-IS owing to introduction of rare earth elements into HLLW were studied. Though rare earth elements exhibit a small influence on the distribution coefficient for Cs+, they impair Cs-exchange capacity of Cs-IS to some extent. This interruption on the selectivity to Cs+ can be significantly eliminated provided an appropriate ratio of liquid to solid V:m is used.

  9. High voltage holding in the negative ion sources with cesium deposition

    Energy Technology Data Exchange (ETDEWEB)

    Belchenko, Yu.; Abdrashitov, G.; Ivanov, A.; Sanin, A.; Sotnikov, O., E-mail: O.Z.Sotnikov@inp.nsk.su [Budker Institute of Nuclear Physics, Siberian Branch of Russian Academy of Sciences, Novosibirsk (Russian Federation)

    2016-02-15

    High voltage holding of the large surface-plasma negative ion source with cesium deposition was studied. It was found that heating of ion-optical system electrodes to temperature >100 °C facilitates the source conditioning by high voltage pulses in vacuum and by beam shots. The procedure of electrode conditioning and the data on high-voltage holding in the negative ion source with small cesium seed are described. The mechanism of high voltage holding improvement by depletion of cesium coverage is discussed.

  10. Specific interaction of cesium with the surface of calcium silicate hydrates

    International Nuclear Information System (INIS)

    The sorption of cesium at the calcium silicate hydrates (CSH) surface was investigated, both through sorption isotherm data and by solid-state NMR experiments. The sorption ability of CSH towards cesium is favored for low solid Ca/Si molar ratios, in agreement with the negative surface charge they develop then. A significant proportion of these sorbed cesium cations remains tightly bound to the surface sites forming, in dehydrated CSH, inner-sphere complexes, which can not be removed by alcohol washing. Chloride seems to present a lower affinity for CSH, even for high Ca/Si molar ratios, where the surface charge becomes positive. (orig.)

  11. First-principles study of cesium adsorption to weathered micaceous clay minerals

    Science.gov (United States)

    Okumura, Masahiko; Nakamura, Hiroki; Machida, Masahiko

    2014-05-01

    A large amount of radioactive nuclides was produced into environment due to the Fukushima Dai-ichi Nuclear Power Plant (FDNPP) accident. Residents near FDNPP were suffering from radioactive cesium and then evacuated, because which has long half-life and is retained by surface soil for long time. The Japanese government has been decontaminating the cesium by removing the surface soil in order to return them to their home. This decontamination method is very effective, but which produces huge amount of waste soil. This becomes another big problem in Fukushima, because it is not easy to find large storage sites. Then effective and economical methods to reduce the volume of the waste soil are needed. However, it has not been invented yet. One of the reasons is lack of knowledge about microscopic process of adsorption/desorption of cesium to/from soil. It is known that weathered micaceous clay minerals play crucial role on adsorption and retention of cesium. They are expected to have special sorption sites, called frayed edge sites (FESs), which adsorb cesium selectively and irreversibly. Properties of FES have been intensely investigated by experiments. But microscopic details of the adsorption process on FES are still unclear. Because direct observation of the process with current experimental techniques is quite difficult. We investigated the adsorption of cesium to FES in muscovite, which is a typical micaceous clay mineral, via first-principles calculations (density functional theory). We made a minimal model of FES and evaluate the energy difference before and after cesium adsorption to FES. This is the first numerical modeling of FES. It was shown that FES does adsorb cesium if the weathering of muscovite has been weathered. In addition, we revealed the mechanism of cesium adsorption to FES, which is competition between ion radius of cesium and the degree of weathering. I plan to discuss volume reduction of the waste soil based on our result. Reference M. Okumura

  12. Test procedures and instructions for single shell tank saltcake cesium removal with crystalline silicotitanate

    Energy Technology Data Exchange (ETDEWEB)

    Duncan, J.B.

    1997-01-07

    This document provides specific test procedures and instructions to implement the test plan for the preparation and conduct of a cesium removal test, using Hanford Single Shell Tank Saltcake from tanks 24 t -BY- I 10, 24 1 -U- 108, 24 1 -U- 109, 24 1 -A- I 0 1, and 24 t - S-102, in a bench-scale column. The cesium sorbent to be tested is crystalline siticotitanate. The test plan for which this provides instructions is WHC-SD-RE-TP-024, Hanford Single Shell Tank Saltcake Cesium Removal Test Plan.

  13. A New Pumping-Probing Scheme for the Optically Pumped Cesium Beam Frequency Standard

    Institute of Scientific and Technical Information of China (English)

    陈景标; 朱程锦; 王凤芝; 杨东海

    2001-01-01

    A new pumping-probing scheme for the optically pumped cesium beam frequency standard has been experimentally tested in our laboratory. The stability of the optically pumped cesium beam frequency standard was measured by comparing its 10 MHz output with an HP5071A commercial cesium atomic clock. The result shows that the frequency stability for the 1 s and 30000s sample times are 1.2 × 10-11 and 3.7 × 10-13, respectively. It was proved that the new pumping scheme works well.

  14. Investigation of adsorption and wetting of 3He on cesium and cesiated glass

    International Nuclear Information System (INIS)

    Experiments have been carried out to investigate the binding of 3He on cesium substrates, using optical pumping to spin-polarize the atoms. The behavior of 3He on the walls at low temperature can be analyzed through the evolution of the nuclear magnetization of the sample. Preliminary results are presented, including: (1) adsorption studies of gaseous 3He on cesiated glass; (2) magnetic relaxation time of polarized liquid 3He on cesium and cesiated glass; (3) evidence for wetting of liquid 3He on cesium. 8 refs., 2 figs

  15. Comparison of biotic and abiotic treatment approaches for co-mingled perchlorate, nitrate, and nitramine explosives in groundwater

    Science.gov (United States)

    Schaefer, C. E.; Fuller, M. E.; Condee, C. W.; Lowey, J. M.; Hatzinger, P. B.

    2007-01-01

    Biological and abiotic approaches for treating co-mingled perchlorate, nitrate, and nitramine explosives in groundwater were compared in microcosm and column studies. In microcosms, microscale zero-valent iron (mZVI), nanoscale zero-valent iron (nZVI), and nickel catalyzed the reduction of RDX and HMX from initial concentrations of 9 and 1 mg/L, respectively, to below detection (0.02 mg/L), within 2 h. The mZVI and nZVI also degraded nitrate (3 mg/L) to below 0.4 mg/L, but none of the metal catalysts were observed to appreciably reduce perchlorate (˜ 5 mg/L) in microcosms. Perchlorate losses were observed after approximately 2 months in columns of aquifer solids treated with mZVI, but this decline appears to be the result of biodegradation rather than abiotic reduction. An emulsified vegetable oil substrate was observed to effectively promote the biological reduction of nitrate, RDX and perchlorate in microcosms, and all four target contaminants in the flow-through columns. Nitrate and perchlorate were biodegraded most rapidly, followed by RDX and then HMX, although the rates of biological reduction for the nitramine explosives were appreciably slower than observed for mZVI or nickel. A model was developed to compare contaminant degradation mechanisms and rates between the biotic and abiotic treatments.

  16. a Biokinetic Model for CESIUM-137 in the Fetus

    Science.gov (United States)

    Jones, Karen Lynn

    1995-01-01

    Previously, there was no method to determine the dose to the embryo, fetus, fetal organs or placenta from radionuclides within the embryo, fetus, or placenta. In the past, the dose to the fetus was assumed to be equivalent to the dose to the uterus. Watson estimated specific absorbed fractions from various maternal organs to the uterine contents which included the fetus, placenta, and amniotic fluid and Sikov estimated the absorbed dose to the embryo/fetus after assuming 1 uCi of radioactivity was made available to the maternal blood.^{1,2} However, this method did not allow for the calculation of a dose to individual fetal organs or the placenta. The radiation dose to the embryo or fetus from Cs-137 in the fetus and placenta due to a chronic ingestion by the mother was determined. The fraction of Cs-137 in the maternal plasma crossing the placenta to the fetal plasma was estimated. The absorbed dose from Cs-137 in each modelled fetal organ was estimated. Since there has been more research regarding potassium in the human body, and particularly in the pregnant woman, a biokinetic model for potassium was developed first and used as a basis and confirmation of the cesium model. Available pertinent information in physiology, embryology, biokinetics, and radiation dosimetry was utilized. Due to the rapid growth of the fetus and placenta, the pregnancy was divided into four gestational periods. The numerous physiological changes that occurred during pregnancy were considered and an appropriate biokinetic model was developed for each of the gestational periods. The amount of cesium in the placenta, embryo, and fetus was estimated for each period. The dose to the fetus from cesium deposited in the embryo or fetus and in the placenta was determined for each period using Medical Internal Radiation Dosimetry (MIRD) methodology. An uncertainty analysis was also performed to account for the variability of the parameters in the biokinetic model based on the experimental data

  17. Diffusion of water, cesium and neptunium in pores of rocks

    International Nuclear Information System (INIS)

    Teollisuuden Voima Oy (TVO) is investigating the feasibility to dispose of spent nuclear fuel within Finland. The present plan calls for the repository to be located in crystalline rock at a depth of several hundred meters. The safety assessment of the repository includes calculations of migration of waste nuclides. The flow of waste elements in groundwater will be retarded through sorption interaction with minerals and through diffusion into rock. Diffusion is the only mechanism retarding the migration of non-sorbing species and, it is expected to be the dominating retardation mechanism of many of the sorbing elements. In the investigation the simultaneous diffusion of tritiated water (HTO), cesium and neptunium in rocks of TVO investigation sites at Kivetty, Olkiluoto and Romuvaara were studied. (11 refs., 33 figs., 9 tabs.)

  18. Cesium-137 accident lessons in Goiania, Goias State, Brazil

    International Nuclear Information System (INIS)

    This document relates the experience obtained by several professionals which had an important role in the cesium-137 accident occurred in Goiania, Goias State, Brazil in September, 1987. It's divided into chapters, according to the action area - medical, nursing, social assistance, odontological and psychological. At first, some notions of radioprotection are explained, followed by the accident history and by the doctors and nurses action during the emergency phase and the medical, odontological, social and psychological assistance to the victims. The social assistance report shows some statistical data about the economic, occupational and social conditions of the accident victims. It is shown some information about the health institutions and the sanitary care in the ionizing radiation and about the occupational radiological protection in Goiania

  19. Coherence Properties of Nanofiber-Trapped Cesium Atoms

    Science.gov (United States)

    Reitz, D.; Sayrin, C.; Mitsch, R.; Schneeweiss, P.; Rauschenbeutel, A.

    2013-06-01

    We experimentally study the ground state coherence properties of cesium atoms in a nanofiber-based two-color dipole trap, localized ˜200nm away from the fiber surface. Using microwave radiation to coherently drive the clock transition, we record Ramsey fringes as well as spin echo signals and infer a reversible dephasing time of T2*=0.6ms and an irreversible dephasing time of T2'=3.7ms. By modeling the signals, we find that, for our experimental parameters, T2* and T2' are limited by the finite initial temperature of the atomic ensemble and the heating rate, respectively. Our results represent a fundamental step towards establishing nanofiber-based traps for cold atoms as a building block in an optical fiber quantum network.

  20. Norbadione A: synthetic approach and cesium complexation studies

    International Nuclear Information System (INIS)

    This work was dedicated to the study of the synthesis and complexation studies of norbadione A: a pigment originating from a mushroom. A synthetic approach, based on a double Suzuki-Miyaura coupling, was developed. This strategy was applied with high yields to the synthesis of various norbadione A analogues, as well as to the synthesis of simple pulvinic acids. Access to functionalized precursors of the molecule was also studied and the final coupling remains to be done. Besides, a speciation study based on electro-spray ionization mass spectrometry was conducted with norbadione A and one of the analogues. This study allowed the assessment of the cesium complexation abilities of each molecule. Structural data was also obtained and complexation constants were calculated. Finally, norbadione A and various synthetic products have been tested via high-throughput screening methods and strong antioxidant properties were observed. Other biological results are also reported. (author)

  1. Vector Cesium Magnetometer for the nEDM Experiment

    International Nuclear Information System (INIS)

    Full text: We use optical pumping combined with magnetic resonance in a Cesium vapor cell in order to measure the magnetic field. A Vector Cs Magnetometer uses multiple laser beams to follow the dynamics of the spin in 3D. The 3D signal is used to extract the Larmor frequency of the spins, and to extract the direction of the magnetic field through the path of the spins. The magnetometer was successfully tested in a proof of principle experiment. Its measured performance is ∼50 pT/Hz1/2 for the directions perpendicular to the magnetic field, and ∼500 fT/Hz1/2 for the direction parallel to the magnetic field. (author)

  2. Coherence properties of nanofiber-trapped cesium atoms

    CERN Document Server

    Reitz, D; Mitsch, R; Schneeweiss, P; Rauschenbeutel, A

    2013-01-01

    We experimentally study the ground state coherence properties of cesium atoms in a nanofiber-based two-color dipole trap, localized 200 nm away from the fiber surface. Using microwave radiation to coherently drive the clock transition, we record Ramsey fringes as well as spin echo signals and infer a reversible dephasing time $T_2^\\ast=0.6$ ms and an irreversible dephasing time $T_2^\\prime=3.7$ ms. By theoretically modelling the signals, we find that, for our experimental parameters, $T_2^\\ast$ and $T_2^\\prime$ are limited by the finite initial temperature of the atomic ensemble and the heating rate, respectively. Our results represent a fundamental step towards establishing nanofiber-based traps for cold atoms as a building block in an optical fiber quantum network.

  3. Quantitative analysis of cesium in synthetic lithium molten salts

    International Nuclear Information System (INIS)

    An analytical technique for fission products in lithium molten salts of spent PWR (Pressurized Water Reactor) fuels has been studied for the establishment of optimum chemical engineering process and the evaluation of process material balance in developing Direct Oxide Reduction Process with lithium metal. As part of the basic research, synthetic dissolver solutions of lithium chloride containing trace amounts of fission product elements (La, Ce, Pr, Nd, Sm, Eu, Gd, Y, Cs, Ru, Rh, Pd, Mo, Zr, Cd, Ba, Sr, Te and Se) was prepared and used in establishing the selective separation technique of cesium from lithium chloride matrix using cation exchange chromatography. Its recovery was measured by flame atomic absorption spectrometry and the reliability of this technique was evaluate

  4. Elastic scattering of sodium and cesium atoms at ultracold temperatures

    Institute of Scientific and Technical Information of China (English)

    Zhang Ji-Cai; Wang Ke-Dong; Liu Yu-Fang; Sun Jin-Feng

    2011-01-01

    The elastic scattering properties in a mixture of sodium and cesium atoms are investigated at cold and ultracold temperatures. Based on the accurate interatomic potential for the NaCs mixture,the interspecies s-wave scattering lengths,the effective ranges and the p-wave scattering lengths are calculated by the quantal method and the semiclassical method,respectively. The s-wave scattering lengths are 512.7ao for the singlet state and 33.4ao for the triplet state. In addition,the spin-change and elastic cross sections are also calculated,and the g-wave shape resonance is found in the total elastic cross sections.

  5. Vitrification of cesium-contaminated organic ion exchange resin

    Energy Technology Data Exchange (ETDEWEB)

    Sargent, T.N. Jr. [Clemson Univ., SC (United States)

    1994-08-01

    Vitrification has been declared by the Environmental Protection Agency (USEPA) as the Best Demonstrated Available Technology (BDAT) for the permanent disposal of high-level radioactive waste. Savannah River Site currently uses a sodium tetraphenylborate (NaTPB) precipitation process to remove Cs-137 from a wastewater solution created from the processing of nuclear fuel. This process has several disadvantages such as the formation of a benzene waste stream. It has been proposed to replace the precipitation process with an ion exchange process using a new resorcinol-formaldehyde resin developed by Savannah River Technical Center (SRTC). Preliminary tests, however, showed that problems such as crust formation and a reduced final glass wasteform exist when the resin is placed in the melter environment. The newly developed stirred melter could be capable of overcoming these problems. This research explored the operational feasibility of using the stirred tank melter to vitrify an organic ion exchange resin. Preliminary tests included crucible studies to determine the reducing potential of the resin and the extent of oxygen consuming reactions and oxygen transfer tests to approximate the extent of oxygen transfer into the molten glass using an impeller and a combination of the impeller and an external oxygen transfer system. These preliminary studies were used as a basis for the final test which was using the stirred tank melter to vitrify nonradioactive cesium loaded organic ion exchange resin. Results from this test included a cesium mass balance, a characterization of the semi-volatile organic compounds present in the off gas as products of incomplete combustion (PIC), a qualitative analysis of other volatile metals, and observations relating to the effect the resin had on the final redox state of the glass.

  6. Light and variable 37Cl/35Cl ratios in rocks from Gale Crater, Mars: Possible signature of perchlorate

    Science.gov (United States)

    Farley, K. A.; Martin, P.; Archer, P. D.; Atreya, S. K.; Conrad, P. G.; Eigenbrode, J. L.; Fairén, A. G.; Franz, H. B.; Freissinet, C.; Glavin, D. P.; Mahaffy, P. R.; Malespin, C.; Ming, D. W.; Navarro-Gonzalez, R.; Sutter, B.

    2016-03-01

    Cl isotope ratios measured on HCl thermally evolved from as-yet-unknown phases in sedimentary rocks and sand in Gale Crater provide unexpected insights to the Martian surficial Cl cycle. The seven samples yield δ37Cl values ranging from - 1 ± 25 ‰ to - 51 ± 5 ‰. Five analyses from two samples of the Sheepbed mudstone (Yellowknife Bay study area) are analytically indistinguishable with a mean δ37Cl of - 11 ± 7 ‰ (1 σ). In contrast, four mudstones/sandstones from the Kimberley and Pahrump study areas also yielded indistinguishable ratios, but with a mean δ37Cl of - 43 ± 6 ‰. The Rocknest sand deposit gave a highly uncertain δ37Cl value of - 7 ± 44 ‰. These light and highly variable δ37Cl values are unique among known solar system materials. Two endmember models are offered to account for these observations, and in both, perchlorate, with its extreme ability to fractionate Cl isotopes, is critical. In the first model, SAM is detecting HCl from an oxychlorine compound (e.g., perchlorate) produced from volcanic gas emissions by atmospheric chemical reactions. Similar reactions in Earth's atmosphere may be responsible for the isotopically lightest known Cl outside of this study, in perchlorate from the Atacama Desert. Some of the Gale Crater δ37Cl values are more negative than those in Atacama perchlorate, but because reaction mechanisms and associated fractionation factors are unknown, it is impossible to assess whether this difference is prohibitive. If the negative δ37Cl signal is produced in this fashion, the isotopic variability among samples could arise either from variations in the relative size of the reactant chloride and product perchlorate reservoirs, or from variations in the fraction of perchlorate reduced back to chloride after deposition. Such reduction strongly enriches 37Cl in the residual perchlorate. Perchlorate reduction alone offers an alternative endmember model that can explain the observed data if SAM measured HCl derived

  7. The Effects of Perchlorates on the Permafrost Methanogens: Implication for Autotrophic Life on Mars.

    Science.gov (United States)

    Shcherbakova, Viktoria; Oshurkova, Viktoria; Yoshimura, Yoshitaka

    2015-01-01

    The terrestrial permafrost represents a range of possible cryogenic extraterrestrial ecosystems on Earth-like planets without obvious surface ice, such as Mars. The autotrophic and chemolithotrophic psychrotolerant methanogens are more likely than aerobes to function as a model for life forms that may exist in frozen subsurface environments on Mars, which has no free oxygen, inaccessible organic matter, and extremely low amounts of unfrozen water. Our research on the genesis of methane, its content and distribution in permafrost horizons of different ages and origin demonstrated the presence of methane in permanently frozen fine-grained sediments. Earlier, we isolated and described four strains of methanogenic archaea of Methanobacterium and Methanosarcina genera from samples of Pliocene and Holocene permafrost from Eastern Siberia. In this paper we study the effect of sodium and magnesium perchlorates on growth of permafrost and nonpermafrost methanogens, and present evidence that permafrost hydogenotrophic methanogens are more resistant to the chaotropic agent found in Martian soil. In this paper we study the effect of sodium and magnesium perchlorates on the growth of permafrost and nonpermafrost methanogens, and present evidence that permafrost hydogenotrophic methanogens are more resistant to the chaotropic agent found in Martian soil. Furthermore, as shown in the studies strain M2(T) M. arcticum, probably can use perchlorate anion as an electron acceptor in anaerobic methane oxidation. Earth's subzero subsurface environments are the best approximation of environments on Mars, which is most likely to harbor methanogens; thus, a biochemical understanding of these pathways is expected to provide a basis for designing experiments to detect autotrophic methane-producing life forms on Mars. PMID:27682103

  8. The Effects of Perchlorates on the Permafrost Methanogens: Implication for Autotrophic Life on Mars.

    Science.gov (United States)

    Shcherbakova, Viktoria; Oshurkova, Viktoria; Yoshimura, Yoshitaka

    2015-01-01

    The terrestrial permafrost represents a range of possible cryogenic extraterrestrial ecosystems on Earth-like planets without obvious surface ice, such as Mars. The autotrophic and chemolithotrophic psychrotolerant methanogens are more likely than aerobes to function as a model for life forms that may exist in frozen subsurface environments on Mars, which has no free oxygen, inaccessible organic matter, and extremely low amounts of unfrozen water. Our research on the genesis of methane, its content and distribution in permafrost horizons of different ages and origin demonstrated the presence of methane in permanently frozen fine-grained sediments. Earlier, we isolated and described four strains of methanogenic archaea of Methanobacterium and Methanosarcina genera from samples of Pliocene and Holocene permafrost from Eastern Siberia. In this paper we study the effect of sodium and magnesium perchlorates on growth of permafrost and nonpermafrost methanogens, and present evidence that permafrost hydogenotrophic methanogens are more resistant to the chaotropic agent found in Martian soil. In this paper we study the effect of sodium and magnesium perchlorates on the growth of permafrost and nonpermafrost methanogens, and present evidence that permafrost hydogenotrophic methanogens are more resistant to the chaotropic agent found in Martian soil. Furthermore, as shown in the studies strain M2(T) M. arcticum, probably can use perchlorate anion as an electron acceptor in anaerobic methane oxidation. Earth's subzero subsurface environments are the best approximation of environments on Mars, which is most likely to harbor methanogens; thus, a biochemical understanding of these pathways is expected to provide a basis for designing experiments to detect autotrophic methane-producing life forms on Mars.

  9. The Effects of Perchlorates on the Permafrost Methanogens: Implication for Autotrophic Life on Mars

    Directory of Open Access Journals (Sweden)

    Viktoria Shcherbakova

    2015-09-01

    Full Text Available The terrestrial permafrost represents a range of possible cryogenic extraterrestrial ecosystems on Earth-like planets without obvious surface ice, such as Mars. The autotrophic and chemolithotrophic psychrotolerant methanogens are more likely than aerobes to function as a model for life forms that may exist in frozen subsurface environments on Mars, which has no free oxygen, inaccessible organic matter, and extremely low amounts of unfrozen water. Our research on the genesis of methane, its content and distribution in permafrost horizons of different ages and origin demonstrated the presence of methane in permanently frozen fine-grained sediments. Earlier, we isolated and described four strains of methanogenic archaea of Methanobacterium and Methanosarcina genera from samples of Pliocene and Holocene permafrost from Eastern Siberia. In this paper we study the effect of sodium and magnesium perchlorates on growth of permafrost and nonpermafrost methanogens, and present evidence that permafrost hydogenotrophic methanogens are more resistant to the chaotropic agent found in Martian soil. In this paper we study the effect of sodium and magnesium perchlorates on the growth of permafrost and nonpermafrost methanogens, and present evidence that permafrost hydogenotrophic methanogens are more resistant to the chaotropic agent found in Martian soil. Furthermore, as shown in the studies strain M2T M. arcticum, probably can use perchlorate anion as an electron acceptor in anaerobic methane oxidation. Earth’s subzero subsurface environments are the best approximation of environments on Mars, which is most likely to harbor methanogens; thus, a biochemical understanding of these pathways is expected to provide a basis for designing experiments to detect autotrophic methane-producing life forms on Mars.

  10. Candlestick oven with a silica wick provides an intense collimated cesium atomic beam

    Science.gov (United States)

    Pailloux, A.; Alpettaz, T.; Lizon, E.

    2007-02-01

    This article shows that readily available glass and silica fibers and braids are suitable capillary structure for recirculating ovens, such as candlestick ovens, becoming then an alternative wick material to conventional metal based capillary structures. In order to study wettability and capillarity of metallic liquid cesium on borosilicate and silica microstructures, samples were selected, prepared, and tested experimentally. The contact angle of cesium on silica glass was roughly measured: θ =35°±10°. A commercially available silica braid was then introduced inside a candlestick oven to transfer the metallic liquid cesium from the cold reservoir to the hot emission point of the candlestick. A collimated cesium atomic beam of intensity of 2×1016at./ssr was obtained, stable and reproducible. Furthermore, this modified oven is easy to handle daily.

  11. Preparation, structure and application of a new ecomaterials cesium ion-sieve

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    A new ecomaterials cesium ion-sieve (Cs-IS), which has high selectivity to cesium and excellent acid resistance, is prepared with zirconyl molybdopyrophosphate as its matrix by specific chemical sieve-making means. Cs-IS has large exchange capacity ( 1.83mmol@g-1) and high distribution coefficient (4.09 x 104 mL@ L-1) in the medium of 3 mol@ L- 1 HNO3. In the static exchange with strongly acidic high-level radioactive liquid waste (HLLW) (3 mol@ L-1 HNO3), Cs-IS exhibits high exchange rate for cesium (above 96.53 % ) and large separation factor (greater than 958.41). These indicate the possible use of Cs-IS in cesium-137 selective removal and recovery from highly saline acidic HLLW system.

  12. Prussian blue caged in spongiform adsorbents using diatomite and carbon nanotubes for elimination of cesium.

    Science.gov (United States)

    Hu, Baiyang; Fugetsu, Bunshi; Yu, Hongwen; Abe, Yoshiteru

    2012-05-30

    We developed a spongiform adsorbent that contains Prussian blue, which showed a high capacity for eliminating cesium. An in situ synthesizing approach was used to synthesize Prussian blue inside diatomite cavities. Highly dispersed carbon nanotubes (CNTs) were used to form CNT networks that coated the diatomite to seal in the Prussian blue particles. These ternary (CNT/diatomite/Prussian-blue) composites were mixed with polyurethane (PU) prepolymers to produce a quaternary (PU/CNT/diatomite/Prussian-blue), spongiform adsorbent with an in situ foaming procedure. Prussian blue was permanently immobilized in the cell walls of the spongiform matrix and preferentially adsorbed cesium with a theoretical capacity of 167 mg/g cesium. Cesium was absorbed primarily by an ion-exchange mechanism, and the absorption was accomplished by self-uptake of radioactive water by the quaternary spongiform adsorbent. PMID:22464752

  13. Synthesis of novel calix[4]crown telomers and selective extraction of cesium ions

    Institute of Scientific and Technical Information of China (English)

    Hai Bing Li; Yuan Yin Chen; De Jun Xiong; Jun Yan Zhan; Cui Ping Han

    2007-01-01

    p-tert-Butylcalix[4]diazacrown-4 telomer, which contains hard and soft ion binding sites, was synthesized. It exhibited high selectivity toward cesium ions. The binding sites may complex alkali metal ions selectively.

  14. Biological effects of cesium-137 injected in beagle dogs of different ages

    Energy Technology Data Exchange (ETDEWEB)

    Nikula, K.J.; Muggenburg, B.A.; Griffith, W.C. [and others

    1995-12-01

    The toxicity of cesium-137 ({sup 137}Cs) in the Beagle dog was investigated at the Argonne National Laboratory (ANL) as part of a program to evaluate the biological effects of internally deposited radionuclides. The toxicity and health effects of {sup 137}Cs are important to understand because {sup 137}Cs is produced in large amounts in light-water nuclear reactors. Large quantities of cesium radioisotopes have entered the human food chain as a result of atmospheric nuclear weapons test, and additional cesium radioisotopes were released during the Chernobyl accident. Although the final analyses are not complete, three findings are significant: older dogs dies significantly earlier than juvenile and young adult dogs; greater occurrence of sarcomas in the cesium-137 injected dogs; the major nonneoplastic effect in dogs surviving beyond 52 d appears to be testicular atrophy.

  15. Total deposition of cesium-137 measured in Finland during the exercise `RESUME 95` in August 1995

    Energy Technology Data Exchange (ETDEWEB)

    Geer, L.E. De; Vintersved, I.; Arntsing, R. [National Defence Research Establisment, Nuclear Detection Group, Stockholm (Sweden)

    1997-12-31

    In the exercise called `RESUME 95` the Nuclear Detection Group from the National Defence Research Establishment in Stockholm participated with field gamma ray measurements combined with soil sampling and profile measurements. The results are presented in this report for the measurements of cesium-137. We considered the measurements of cesium-137 at the airfield the most important part of the in-situ exercise. Data was of course collected also for cesium-134 and natural radionuclides but time has not permitted a full analysis of these radionuclides. The methodology would, however, be the same as applied for cesium-137. Less attention was paid for area II and due to limited personnel resources the search exercise was not fully carried out. (au).

  16. Assessment of food calcium radioprotection effectiveness against cesium-137, added alone and with iodine-131

    International Nuclear Information System (INIS)

    New fish product with addition of food calcium had radioprotective properties, resulted in decreased cesium-137 content in organs and tissues of animals by 40-60% and lesser changes in differential blood count and biochemical indexes of blood serum

  17. Cold cesium molecules produced directly in a magneto-optical trap

    Institute of Scientific and Technical Information of China (English)

    Zhang Hong-Shan; Ji Zhong-Hua; Yuan Jin-Peng; Zhao Yan-Ting; Ma Jie; Wang Li-Rong; Xiao Lian-Tuan; Jia Suo-Tang

    2011-01-01

    We report on the observation of ultracold ground electric-state cesium molecules produced directly in a magnetooptical trap with a good signal-to-noise ratio.These molecules arise from the photoassociation of magneto-optical trap lasers and they are detected by resonantly enhanced multiphoton ionization technology.The production rate of ultracold cesium molecules is up to 4× 104 s-1.We measure the characteristic time of the ground electric-state cesium molecules generated in the experiment and investigate the Cs2+ molecular ion intensity as a function of the trapping laser intensity and the ionization pulse laser energy.We conclude that the production of cold cesium molecules may be enhanced by using appropriate experimental parameters,which is useful for future experiments involving the production and trapping of ultracold ground electric-state molecules.

  18. Cs2 ‘diffuse bands’ emission from superheated cesium vapor

    Science.gov (United States)

    Pichler, G.; Makdisi, Y.; Kokaj, J.; Thomas, N.; Mathew, J.; Beuc, R.

    2016-07-01

    Thermal emission from superheated cesium vapor was studied to very high temperatures from 700 °C to 1000 °C. This was performed in the vapor condition only and with no liquid cesium present in the all-sapphire cell. We observed a number of atomic and molecular spectral features simultaneously in emission and absorption, especially peculiar thermal emission of cesium dimer diffuse bands (2 3Πg → a 3∑u + transitions) around 710 nm coexisting with absorption bands around first resonance lines at 852 and 894 nm. We performed appropriate calculations of the diffuse band emission profiles and compared them with measured profiles. We also performed absorption measurements and compared observed diffuse band profiles with calculated ones. Possible applications of the observed phenomena will be discussed in terms of the solar energy conversion using dense cesium vapor.

  19. Fission of Multiply Charged Cesium and Potassium Clusters in Helium Droplets - Approaching the Rayleigh Limit

    CERN Document Server

    Renzler, Michael; Daxner, Matthias; Kranabetter, Lorenz; Kuhn, Martin; Scheier, Paul; Echt, Olof

    2016-01-01

    Electron ionization of helium droplets doped with cesium or potassium results in doubly and, for cesium, triply charged cluster ions. The smallest observable doubly charged clusters are $Cs_{9}^{2+}$ and $K_{11}^{2+}$; they are a factor two smaller than reported previously. The size of potassium dications approaches the Rayleigh limit nRay for which the fission barrier is calculated to vanish, i.e. their fissilities are close to 1. Cesium dications are even smaller than nRay, implying that their fissilities have been significantly overestimated. Triply charged cesium clusters as small as $Cs_{19}^{3+}$ are observed; they are a factor 2.6 smaller than previously reported. Mechanisms that may be responsible for enhanced formation of clusters with high fissilities are discussed.

  20. Formation of oxidizing species via irradiation of perchlorates using high-energy electrons and D 2 + ions

    Science.gov (United States)

    Crandall, Parker B.; Gillis-Davis, Jeffrey J.; Kaiser, Ralf-Ingo

    2016-10-01

    The perchlorate ion (ClO4–) has garnered particular interest in recent years following the discovery of perchlorate salts in the Martian regolith at levels of 0.4–0.6 wt% by the Phoenix lander in 2006 and Mars Science Laboratory's Curiosity rover in 2013. Due to their oxidizing properties, perchlorates are suspected to play a contributing role to the surprising lack of organics on the Martian surface. In this study, magnesium perchlorate hexahydrate (Mg(ClO4)2●6H2O) samples were irradiated with monoenergetic beams of 5 keV electrons and D2+ ions separately, sequentially, and simultaneously to simulate the effects of galactic cosmic ray exposure of perchlorates. The irradiation experiments were carried out under ultra-high vacuum conditions at 50 K, after which the samples were slowly heated to 300 K (0.5 K min–1) while desorbing products were monitored by quadrupole mass spectrometry. In all cases, molecular oxygen (O2) was detected upon the onset of irradiation and again during the warmup phase. In the case of simultaneous irradiation, deuterated water (D2O) and deuterium peroxide (D2O2) were also detected as the sample was heated whereas in the D2+ experiment small amounts of D2O2 was found exclusively. When samples were irradiated sequentially, the production of D2O2 was dependent upon the sample being irradiated with D2+ ions prior to electrons. These experiments show that perchlorates are capable of producing multiple oxidizing agents (O2, D2O2) which may also account for the lack of organics on the Martian surface.

  1. Bis[N-(2-pyridylcarbonylpyridine-2-carboximidato]iron(III perchlorate methanol solvate

    Directory of Open Access Journals (Sweden)

    Dayu Wu

    2009-11-01

    Full Text Available In the title complex, [Fe(C12H8N3O22]ClO4·CH3OH, the iron(III ion is surrounded by two tridentate N-(2-pyridylcarbonylpyridine-2-carboximidate (bpca ligands and exhibits a distorted octahedral coordination by six bpca N atoms. A classical O—H...O hydrogen bond exists between the methanol solvent molecule and the perchlorate anion. Magnetic susceptibility measurements indicated the complex to be in the low-spin state in the temperature range 5–400 K.

  2. Lanthanide perchlorate complexes of quinoline-1-oxide and isoquinoline-2-oxide

    OpenAIRE

    Kalyanasundaram, R; Navaneetham, NS; Soundararajan, S.

    1985-01-01

    Complexes of lanthanide perchlorates with quinoline-1-oxide and isoquinoline-2-oxide have been isolated for the first time characterised by analysis, conductance and IR, NMR and electronic spectoral studies. The complexes of quinoline-1-oxide have the composition $Ln(QNO)_8$$(ClO_4)_3$ where Ln = La, Pr or Nd and $Ln(QNO)_7$ where Ln = Gd, Dy, Ho, Er, Yb. The isoquinoline-2-oxide complexes analyse for the formula $Ln(IsoQNO)_7(ClO_4)_3$ where Ln = La-Yb.

  3. Zero-Pressure Organic Superconductor: Di-(Tetramethyltetraselenafulvalenium)-Perchlorate [(TMTSF)2ClO4

    DEFF Research Database (Denmark)

    Bechgaard, Klaus; da Costa Carneiro, Kim; Olsen, Malte;

    1981-01-01

    Evidence for superconductivity in the organic conductor di-(tetramethyltetraselenafulvalenium)-perchlorate [(TMTSF)2ClO4] has been found by resistance measurements in the absence of applied pressure. For different crystals the transitions are approximately 0.3 K wide and are centered around tempe...... temperatures between 1.2 and 1.4 K. At 0.9 K, a perpendicular magnetic field of 25 mT nearly restores normal resistance. Below 0.1 K, this critical field exceeds 50 mT....

  4. Purification of human genomic DNA from whole blood using sodium perchlorate in place of phenol.

    Science.gov (United States)

    Johns, M B; Paulus-Thomas, J E

    1989-08-01

    We have developed a new, rapid method for the extraction of human genomic DNA from whole blood samples. Traditionally, genomic DNA has been extracted from blood by overnight proteinase K digestion of lysed peripheral lymphocytes followed by phenol/chloroform extraction. In addition to being time consuming, the use of phenol involves inherent risks due to the toxic nature of the reagent. Our method for the extraction of DNA from whole blood uses sodium perchlorate and chloroform instead of phenol with a significant time savings realized as well as fewer hazards to the technician. Furthermore, DNA prepared by this new method is an excellent substrate for restriction endonuclease digestion and Southern hybridization analysis.

  5. Reanalysis of the Viking results suggests perchlorate and organics at mid-latitudes on Mars

    Science.gov (United States)

    Navarro-Gonzalez, R.; Vargas, E.; de La Rosa, J.; Raga, A. C.; McKay, C.

    2010-12-01

    The most comprehensive search for organics in the Martian soil was performed by the Viking Landers. Martian soil was subjected to a thermal volatilization process in order to vaporize and break organic molecules, and the resultant gases and volatiles were analyzed by gas chromatography-mass spectrometry. Only water at 0.1-1.0 wt% was detected with traces of chloromethane at 15 ppb in the Viking Landing site 1, and water at 0.05-1.0 wt% and carbon dioxide at 50-700 ppm with traces of dichloromethane at 0.04-40 ppb in the Viking Landing site 2. The abundance ratio of the 35Cl and 37Cl isotopes in these chlorohydrocarbons was 3:1, corresponding to the terrestrial isotopic abundance. Therefore, these chlorohydrocarbons were considered to be terrestrial contaminants although they had not been detected at those levels in the blank runs. Recently, perchlorate was discovered in the Martian Arctic soil by the Phoenix Lander. Here we show that when Mars-like soils from the Atacama Desert with 32±6 ppm of organic carbon are mixed with 1 wt% magnesium perchlorate and heated nearly all the organics present are decomposed to water and carbon dioxide, but a small amount are chlorinated forming 1.6 ppm of chloromethane and 0.02 ppm of dichloromethane at 500○C. A chemical kinetics model was developed to predict the degree of oxidation and chlorination of organics in the Viking oven. The isotopic distribution of 35Cl and 37Cl for Mars is not known. Studies on Earth indicate that there is no isotopic fractionation of chlorine in the mantle or crust, despite the fact that it is significantly depleted on the planet as compare to solar abundances. The 37Cl/35Cl isotopic ratio in carbonaceous chondrites is similar to the Earth’s value, which suggests that the terrestrial planets, including Mars, were all formed from a similar reservoir of chlorine species in the presolar nebulae and that there was no further isotopic fractionation during the Earth’s differentiation or late

  6. 2-(2-Hydroxy-3-methoxyphenyl-1H-benzimidazol-3-ium perchlorate

    Directory of Open Access Journals (Sweden)

    Chuan Chen

    2012-06-01

    Full Text Available In the title molecular salt, C14H13N2O2+·ClO4−, the ring systems in the cation are almost coplanar [dihedral angle = 5.53 (13°]. Intramolecular N—H...O and O—H...O hydrogen bonds generate S(6 and S(5 rings, respectively. In the crystal, the two H atoms involved in the intramolecular hydrogen bonds also participate in intermolecular links to acceptor O atoms of the perchlorate anions. A simple intermolecular N—H...O bond also occurs. Together, these form a double-chain structure along [101].

  7. Fabrication and performance of fl y ash granule filter for trapping gaseous cesium

    Directory of Open Access Journals (Sweden)

    Park Jang Jin

    2015-09-01

    Full Text Available Although a disk-type fly ash filter has shown a good performance in trapping gaseous cesium, it has difficulty in charging filters into a filter container and discharging waste filters containing radioactive cesium from a container by remote action. To solve the difficulty of the disk-type fly ash filter, five types of granule filters, including a ball type, tube type, and sponge-structure type have been made. Among them, the best filter type was chosen through simple crucible tests. The five types of granule filters packed into containers were loaded into five alumina crucibles of 50 cc. Five grams of CsNO3 was used as a gaseous cesium source. They were then placed in a muffle furnace and heated to 900°C and maintained for 2 hours. After the experiment, the weights of the cesium trapped filters were measured. Among the five types of granule filters, the sponge-structure type granule filter was the best, which has the highest trapping capacity of cesium. Its capacity is 0.42 g-Cs/g-filter. The chosen sponge-structure type granule filters and disk-type filters have been tested using a two-zone tube furnace. Cs volatilization and Cs trapping zones were maintained at 900 and 1000°C, respectively. Sixteen grams of CsNO3 was used as a gaseous cesium source. The cesium trapping profile of the sponge-structure type granule filters was almost similar to that of the disk-type fly ash filters. For both cases, cesium was successfully trapped within the third filter.

  8. Combined effects of perchlorate, thiocyanate, and iodine on thyroid function in the National Health and Nutrition Examination Survey 2007–08

    Energy Technology Data Exchange (ETDEWEB)

    Steinmaus, Craig, E-mail: craigs@berkeley.edu [Office of Environmental Health Hazard Assessment, California Environmental Protection Agency, 1515 Clay St. 16th Floor, Oakland, CA 94612 (United States); Miller, Mark D., E-mail: ucsfpehsumiller@gmail.com [Office of Environmental Health Hazard Assessment, California Environmental Protection Agency, 1515 Clay St. 16th Floor, Oakland, CA 94612 (United States); Cushing, Lara, E-mail: lara.cushing@berkeley.edu [Energy and Resources Group, 310 Barrows Hall, University of California, Berkeley, CA 93720-3050 (United States); Blount, Benjamin C., E-mail: bkb3@cdc.gov [Division of Laboratory Sciences, National Center for Environmental Health, Centers for Disease Control and Prevention, 4770 Buford Highway, NE, Mail Stop F47, Atlanta, GA (United States); Smith, Allan H., E-mail: ahsmith@berkeley.edu [Arsenic Health Effects Research Group, 1950 Addison St., Suite 204, University of California, Berkeley, CA 94704 (United States)

    2013-05-15

    Perchlorate, thiocyanate, and low iodine intake can all decrease iodide intake into the thyroid gland. This can reduce thyroid hormone production since iodide is a key component of thyroid hormone. Previous research has suggested that each of these factors alone may decrease thyroid hormone levels, but effect sizes are small. We hypothesized that people who have all three factors at the same time have substantially lower thyroid hormone levels than people who do not, and the effect of this combined exposure is substantially larger than the effects seen in analyses focused on only one factor at a time. Using data from the 2007–2008 National Health and Nutrition Examination Survey, subjects were categorized into exposure groups based on their urinary perchlorate, iodine, and thiocyanate concentrations, and mean serum thyroxine concentrations were compared between groups. Subjects with high perchlorate (n=1939) had thyroxine concentrations that were 5.0% lower (mean difference=0.40 μg/dl, 95% confidence interval=0.14–0.65) than subjects with low perchlorate (n=2084). The individual effects of iodine and thiocyanate were even smaller. Subjects with high perchlorate, high thiocyanate, and low iodine combined (n=62) had thyroxine concentrations 12.9% lower (mean difference=1.07 μg/dl, 95% confidence interval=0.55–1.59) than subjects with low perchlorate, low thiocyanate, and adequate iodine (n=376). Potential confounders had little impact on results. Overall, these results suggest that concomitant exposure to perchlorate, thiocyanate, and low iodine markedly reduces thyroxine production. This highlights the potential importance of examining the combined effects of multiple agents when evaluating the toxicity of thyroid-disrupting agents. -- Highlights: ► Recent data suggest that essentially everyone in the US is exposed to perchlorate. ► Perchlorate exposure may be associated with lower thyroid hormone levels. ► Some groups may be more susceptible to

  9. Combined effects of perchlorate, thiocyanate, and iodine on thyroid function in the National Health and Nutrition Examination Survey 2007–08

    International Nuclear Information System (INIS)

    Perchlorate, thiocyanate, and low iodine intake can all decrease iodide intake into the thyroid gland. This can reduce thyroid hormone production since iodide is a key component of thyroid hormone. Previous research has suggested that each of these factors alone may decrease thyroid hormone levels, but effect sizes are small. We hypothesized that people who have all three factors at the same time have substantially lower thyroid hormone levels than people who do not, and the effect of this combined exposure is substantially larger than the effects seen in analyses focused on only one factor at a time. Using data from the 2007–2008 National Health and Nutrition Examination Survey, subjects were categorized into exposure groups based on their urinary perchlorate, iodine, and thiocyanate concentrations, and mean serum thyroxine concentrations were compared between groups. Subjects with high perchlorate (n=1939) had thyroxine concentrations that were 5.0% lower (mean difference=0.40 μg/dl, 95% confidence interval=0.14–0.65) than subjects with low perchlorate (n=2084). The individual effects of iodine and thiocyanate were even smaller. Subjects with high perchlorate, high thiocyanate, and low iodine combined (n=62) had thyroxine concentrations 12.9% lower (mean difference=1.07 μg/dl, 95% confidence interval=0.55–1.59) than subjects with low perchlorate, low thiocyanate, and adequate iodine (n=376). Potential confounders had little impact on results. Overall, these results suggest that concomitant exposure to perchlorate, thiocyanate, and low iodine markedly reduces thyroxine production. This highlights the potential importance of examining the combined effects of multiple agents when evaluating the toxicity of thyroid-disrupting agents. -- Highlights: ► Recent data suggest that essentially everyone in the US is exposed to perchlorate. ► Perchlorate exposure may be associated with lower thyroid hormone levels. ► Some groups may be more susceptible to

  10. Enhanced electronic injection in organic light-emitting diodes by incorporating silver nanoclusters and cesium carbonate

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Ying-Chung; Gao, Chia-Yuan [Department of Electrical Engineering, National Sun Yat-Sen University, Kaohsiung, Taiwan (China); Chen, Kan-Lin [Department of Electronic Engineering, Fortune Institute of Technology, Kaohsiung, Taiwan (China); Sze, Po-Wen [Department of Electro-Optical Science and Engineering, Kao Yuan University, Kaohsiung, Taiwan (China); Huang, Chien-Jung, E-mail: chien@nuk.edu.tw [Department of Applied Physics, National University of Kaohsiung, Kaohsiung, Taiwan (China)

    2015-10-01

    Highlights: • The localized electric field around SNCs is enhanced. • When the cesium carbonate/silver nanoclusters/cesium carbonate electron-injection structure replaces the cesium carbonate electron-injection structure, higher electron-injection ability is obtained. • The structure for efficient electron injection is critical to characteristics of the device. - Abstract: The influence of the cesium carbonate/silver nanoclusters/cesium carbonate electron-injection structure (CSC-EIS) on the performance of organic light-emitting diodes is investigated in this study. The silver nanoclusters (SNCs) are introduced between the electron-injection layers by means of thermal evaporation. When the CSC-EIS replaces the cesium carbonate electron-injection structure, higher electron-injection ability is obtained because the electron-injection barrier between the cathode and the electron-transport layer is remarkably reduced from 1.2 to 0 eV. In addition, surface plasmon resonance effect will cause the enhanced localized electric field around the SNCs, resulting that electron-injection ability is further enhanced from the cathode to the emitting layer.

  11. Measurement of cesium emissions during the vitrification of simulated high level radioactive waste

    International Nuclear Information System (INIS)

    In the Defense Waste Processing Facility at the Savannah River Site, it is desired to eliminate a startup test that would involve adding small amounts of radioactive cesium-137 to simulated high-level waste. In order to eliminate this test, a reliable method for measuring non-radioactive cesium in the offgas system from the glass melter is required. From a pilot scale melter system, offgas particulate samples were taken on filter paper media and analyzed by Inductively Coupled Plasma-Mass Spectrometry (ICP-MS). The ICPMS method proved to be sufficiently sensitive to measure cesium quantities as low as 0.135 μg, with the sensitivity being limited by the background cesium present in the filter paper. Typical particulate loadings ranged from 800 μg of cesium. This sensitivity allowed determination of cesium decontamination factors for four of the five major components of the offgas system. The decontamination factors measured experimentally compared favorably with the process design basis values

  12. Modeling Ion-Exchange Processing With Spherical Resins For Cesium Removal

    Energy Technology Data Exchange (ETDEWEB)

    Hang, T.; Nash, C. A.; Aleman, S. E.

    2012-09-19

    The spherical Resorcinol-Formaldehyde and hypothetical spherical SuperLig(r) 644 ion-exchange resins are evaluated for cesium removal from radioactive waste solutions. Modeling results show that spherical SuperLig(r) 644 reduces column cycling by 50% for high-potassium solutions. Spherical Resorcinol Formaldehyde performs equally well for the lowest-potassium wastes. Less cycling reduces nitric acid usage during resin elution and sodium addition during resin regeneration, therefore, significantly decreasing life-cycle operational costs. A model assessment of the mechanism behind ''cesium bleed'' is also conducted. When a resin bed is eluted, a relatively small amount of cesium remains within resin particles. Cesium can bleed into otherwise decontaminated product in the next loading cycle. The bleed mechanism is shown to be fully isotherm-controlled vs. mass transfer controlled. Knowledge of residual post-elution cesium level and resin isotherm can be utilized to predict rate of cesium bleed in a mostly non-loaded column. Overall, this work demonstrates the versatility of the ion-exchange modeling to study the effects of resin characteristics on processing cycles, rates, and cold chemical consumption. This evaluation justifies further development of a spherical form of the SL644 resin.

  13. Prussian blue caged in spongiform adsorbents using diatomite and carbon nanotubes for elimination of cesium

    International Nuclear Information System (INIS)

    Highlights: ► Prussian blue was sealed in cavities of diatomite using carbon nanotubes. ► The caged Prussian blue after being permanently immobilized in polyurethane spongy showed a 167 mg/g capability for absorbing cesium. ► Cesium elimination was accomplished by simply adding the Prussian-blue based spongiform adsorbent to radioactive water. - Abstract: We developed a spongiform adsorbent that contains Prussian blue, which showed a high capacity for eliminating cesium. An in situ synthesizing approach was used to synthesize Prussian blue inside diatomite cavities. Highly dispersed carbon nanotubes (CNTs) were used to form CNT networks that coated the diatomite to seal in the Prussian blue particles. These ternary (CNT/diatomite/Prussian-blue) composites were mixed with polyurethane (PU) prepolymers to produce a quaternary (PU/CNT/diatomite/Prussian-blue), spongiform adsorbent with an in situ foaming procedure. Prussian blue was permanently immobilized in the cell walls of the spongiform matrix and preferentially adsorbed cesium with a theoretical capacity of 167 mg/g cesium. Cesium was absorbed primarily by an ion-exchange mechanism, and the absorption was accomplished by self-uptake of radioactive water by the quaternary spongiform adsorbent.

  14. Prussian blue caged in spongiform adsorbents using diatomite and carbon nanotubes for elimination of cesium

    Energy Technology Data Exchange (ETDEWEB)

    Hu, Baiyang [Graduate School of Environmental Science, Hokkaido University, Sapporo 060-0810 (Japan); Fugetsu, Bunshi, E-mail: hu@ees.hokudai.ac.jp [Graduate School of Environmental Science, Hokkaido University, Sapporo 060-0810 (Japan); Yu, Hongwen [Graduate School of Environmental Science, Hokkaido University, Sapporo 060-0810 (Japan); Abe, Yoshiteru [Kyoei Engineering Corporation, Niigata 959-1961 (Japan)

    2012-05-30

    Highlights: Black-Right-Pointing-Pointer Prussian blue was sealed in cavities of diatomite using carbon nanotubes. Black-Right-Pointing-Pointer The caged Prussian blue after being permanently immobilized in polyurethane spongy showed a 167 mg/g capability for absorbing cesium. Black-Right-Pointing-Pointer Cesium elimination was accomplished by simply adding the Prussian-blue based spongiform adsorbent to radioactive water. - Abstract: We developed a spongiform adsorbent that contains Prussian blue, which showed a high capacity for eliminating cesium. An in situ synthesizing approach was used to synthesize Prussian blue inside diatomite cavities. Highly dispersed carbon nanotubes (CNTs) were used to form CNT networks that coated the diatomite to seal in the Prussian blue particles. These ternary (CNT/diatomite/Prussian-blue) composites were mixed with polyurethane (PU) prepolymers to produce a quaternary (PU/CNT/diatomite/Prussian-blue), spongiform adsorbent with an in situ foaming procedure. Prussian blue was permanently immobilized in the cell walls of the spongiform matrix and preferentially adsorbed cesium with a theoretical capacity of 167 mg/g cesium. Cesium was absorbed primarily by an ion-exchange mechanism, and the absorption was accomplished by self-uptake of radioactive water by the quaternary spongiform adsorbent.

  15. The effects of K+ growth conditions on the accumulation of cesium by the bacterium Thermus sp. TibetanG6

    Institute of Scientific and Technical Information of China (English)

    WANG; Hailei; KONG; Fanjing; ZHENG; Mianping

    2006-01-01

    The accumulation of cesium by the bacterium Thermus sp. TibetanG6 was examined under different K+ growth conditions. The effects of external pH and Na+ on the accumulation of cesium were also studied, and the mechanism involved was discussed. K+ regimes played an important role in the accumulation of cesium by the strain TibetanG6. The quantity of cesium accumulated (24 h) was much higher in K+-deficient regime than that in K+-sufficient regime. The pH and Na+ had different effects on the accumulation of cesium in the two K+ regimes. IR spectra analyses indicated that the biosorption is a process of homeostasis with cesium initially accumulated on the cell wall.

  16. Monitoring of radionuclides in the environment. Part. 4. Factors influencing depth profiles of radioactive cesium in soils

    International Nuclear Information System (INIS)

    In order to evaluate the vertical migration behavior of radioactive cesium, which contaminated by the Fukushima Dai-ichi NPP accident, the distribution of radioactive cesium in different type of soils, e.g., bare ground, grass land, conifer forest floor were measured on October 2011, 2012, 2013, in Abiko, Chiba, Japan. Even three years after the deposition, most of radioactive cesium were deposited in the depths of within 5 cm at anywhere in this area. Depth profiles of radioactive cesium in soil was significantly correlated with organic matter content in soils (r=0.82; p<0.0001), whereas the factors such as potassium ion and ammonium ion in soil, stable cesium content, and clay mineral content were not correlated clearly. This indicates that the vertical migration rate of radioactive cesium is very slow and it would be influenced by organic matter in soil, not just clay. (author)

  17. Adsorption of Chloride,Nitrate and Perchlorate by Variable Charge Soils

    Institute of Scientific and Technical Information of China (English)

    JIGUO-LIANG; KONGXIAO-LING

    1992-01-01

    Two cells consisting of a chloride-selective eloectrode and a nitrate-selective electrode or of a chloride-selectrive electrode and a perchlorate-selective electrode were directly put in the soil suspension to determine the concentration rations Cl-/NO3- or Cl-/ClO4- for studying the adsorption of the three anions by variable charge soils.It was found that all the concentration ration CCl-/CNO3- and CCl-/CClO4- in suspension were smaller than unity when soil samples were in equilibrium with mixed KCl and KNO3 or KCl and KClO4 solutions of equal concentration.The order of the amount of chloride,nitrate and perchlorate adsorbed by variable charge soils was Cl->NO3->ClO4- when the soils adsorbed these anions from the solution containing equal concentrations of Cl-,NO3- and ClO4-.Such factors as the pH of the suspension,the iron oxide content of the soil etc.Could affect the amounts and the ratios of anions adsorbed.The adsorption was chiefly caused by coulombic attraction,but a covalent force between the anion and the metal atom on the surface of soil particles may also be involved,at least for Cl- ions,even for NO3- ions.

  18. 123Iodine scintigraphy and perchlorate discharge test in the diagnosis of congenital hypothyroidism

    International Nuclear Information System (INIS)

    Aim: Thirty eight children suffering from congenital primary permanent hypothyroidism were studied to determine the diagnostic impact of 123I scintigraphy in comparison to laboratory findings and ultrasonography. Methods: In all patients 123I scintigraphy was performed after intravenous administration of 3,7 MBq 123I. If accumulation of the radiotracer in thyroid tissue occured a perchlorate discharge test was performed subsequently. Results: Scintigraphy revealed athyrosis in 7 children. In 9 children a lingual thyroid was observed. Deficiency in iodine organification was diagnosed by a significant discharge of 123I in 15 patients. In four of these children the diagnosis of Pendred's syndrome could be established. Ectopic thyroid tissue could be demonstrated only by scintigraphy where clinical examination and sonography failed in the diagnosis in all cases. Hypoplasia of the thyroid gland as it was diagnosed in 2 cases by ultrasonography appeared to be unlikely because of normal 123I uptake was seen in these patients. In 2 patients with scintigraphic proven athyrosis an orthotopic gland had been falsely considered by ultrasound. In 44% of our patients the final diagnosis could only be established if 123I scintigraphy and perchlorate discharge test were performed. Conclusion: This findings suggest that scintigraphy is indispensible in the correct diagnostic work up of congenital hypothyroidism. (orig.)

  19. Change of iodine load and thyroid homeostasis induced by ammonium perchlorate in rats.

    Science.gov (United States)

    Chen, Hong-Xia; Ding, Miao-Hong; Liu, Qin; Peng, Kai-Liang

    2014-10-01

    Ammonium perchlorate (AP), mainly used as solid propellants, was reported to interfere with homeostasis via competitive inhibition of iodide uptake. However, detailed mechanisms remain to be elucidated. In this study, AP was administered at 0, 130, 260 and 520 mg/kg every day to 24 male SD rats for 13 weeks. The concentrations of iodine in urine, serum thyroid hormones levels, total iodine, relative iodine and total protein, and malondialdehyde (MDA), superoxide dismutase (SOD) and catalase (CAT) activity in thyroid tissues were measured, respectively. Our results showed that high-dose perchlorate induced a significant increase in urinary iodine and serum thyroid stimulating hormone (TSH), with a decrease of total iodine and relative iodine content. Meanwhile, free thyroxine (FT4) was decreased and CAT activity was remarkably increased. Particularly, the CAT activity was increased in a dose-dependent manner. These results suggested that CAT might be enhanced to promote the synthesis of iodine, resulting in elevated urinary iodine level. Furthermore, these findings suggested that iodine in the urine and CAT activity in the thyroid might be used as biomarkers for exposure to AP, associated with thyroid hormone indicators such as TSH, FT4.

  20. Nano-Ammonium Perchlorate: Preparation, Characterization, and Evaluation in Composite Propellant Formulation

    Science.gov (United States)

    Kumari, A.; Mehilal; Jain, S.; Jain, M. K.; Bhattacharya, B.

    2013-07-01

    Nanomaterials are finding applications in explosives and propellant formulations due to their large surface area and high surface energy. This high surface energy is responsible for the low activation energy and increase in burning rate of the composition. Therefore, a successful attempt has been made to prepare nano-ammonium perchlorate using a nonaqueous method by dissolving ammonium perchlorate (AP) in methanol followed by adding the dissolved AP to the hydroxyl-terminated polybutadiene (HTPB), homogenization, and vacuum distillation of the solvent. The nano-AP thus formed was characterized using a NANOPHOX particle size analyzer (Sympatec, Germany), transmission electron microscopy (FEI, Hillsboro, OR), X-ray diffraction (PANalytical B.V., The Netherlands) and scanning electron microscopy (Ikon Analytical Equipment Pvt. Ltd., Mumbai, India) for particle size, purity, and morphology, respectively. The thermal behavior of nano-AP was also studied using differential thermal analysis-thermo gravimetric analysis (DTA-TGA). The data indicated that the particle size of the prepared AP was in the range of 21-52 nm and the thermal decomposition temperature was lower than that of coarse AP. Characterized nano-AP was subsequently used in composite propellant formulation up to 5% with 86% solid loading and studied for different properties. The results showed a 14% increase in burning rate in comparison to standard propellant composition with desired mechanical properties.

  1. Interfacial behavior of perchlorate versus chloride ions in saturated aqueous salt solutions

    Energy Technology Data Exchange (ETDEWEB)

    Ghosal, S; Kuo, I W; Baer, M D; Bluhm, H

    2009-04-14

    In recent years combination of theoretical and experimental work have presented a novel view of the aqueous interface wherein hard and/or multiply charged ions are excluded from the interface, but large polarizable anions show interfacial enhancement relative to the bulk. The observed trend in the propensity of anions to adsorb at the air/water interface appears to be reverse of the Hofmeister series for anions. This study focuses on experimental and theoretical examination of the partitioning behavior of perchlorate (ClO{sub 4}{sup -}) and chloride (Cl{sup -}) ions at the air/water interface. We have used ambient pressure X-ray photoelectron spectroscopy technique to directly probe the interfacial concentrations of ClO{sub 4}{sup -} and Cl{sup -} ions in sodium perchlorate and sodium chloride solutions, respectively. Experimental observations are compared with first principles molecular dynamics simulations. Both experimental and simulation results show enhancement of ClO{sub 4}{sup -} ion at the interface, compared with the absence of such enhancement in the case of Cl{sup -} ion. These observations are in agreement with the expected trend in the interfacial propensity of anions based on the Hofmeister series.

  2. Engineered Materials for Cesium and Strontium Storage Final Technical Report

    Energy Technology Data Exchange (ETDEWEB)

    Sean M. McDeavitt

    2010-04-14

    Closing the nuclear fuel cycle requires reprocessing spent fuel to recover the long-lived components that still have useful energy content while immobilizing the remnant waste fission products in stable forms. At the genesis of this project, next generation spent fuel reprocessing methods were being developed as part of the U.S. Department of Energy's Advanced Fuel Cycle Initiative. One of these processes was focused on solvent extraction schemes to isolate cesium (Cs) and strontium (Sr) from spent nuclear fuel. Isolating these isotopes for short-term decay storage eases the design requirements for long-term repository disposal; a significant amount of the radiation and decay heat in fission product waste comes from Cs-137 and Sr-90. For the purposes of this project, the Fission Product Extraction (FPEX) process is being considered to be the baseline extraction method. The objective of this project was to evaluate the nature and behavior of candidate materials for cesium and strontium immobilization; this will include assessments with minor additions of yttrium, barium, and rubidium in these materials. More specifically, the proposed research achieved the following objectives (as stated in the original proposal): (1) Synthesize simulated storage ceramics for Cs and Sr using an existing labscale steam reformer at Purdue University. The simulated storage materials will include aluminosilicates, zirconates and other stable ceramics with the potential for high Cs and Sr loading. (2) Characterize the immobilization performance, phase structure, thermal properties and stability of the simulated storage ceramics. The ceramic products will be stable oxide powders and will be characterized to quantify their leach resistance, phase structure, and thermophysical properties. The research progressed in two stages. First, a steam reforming process was used to generate candidate Cs/Sr storage materials for characterization. This portion of the research was carried out at

  3. Engineered Materials for Cesium and Strontium Storage. Final Technical Report

    International Nuclear Information System (INIS)

    Closing the nuclear fuel cycle requires reprocessing spent fuel to recover the long-lived components that still have useful energy content while immobilizing the remnant waste fission products in stable forms. At the genesis of this project, next generation spent fuel reprocessing methods were being developed as part of the U.S. Department of Energy's Advanced Fuel Cycle Initiative. One of these processes was focused on solvent extraction schemes to isolate cesium (Cs) and strontium (Sr) from spent nuclear fuel. Isolating these isotopes for short-term decay storage eases the design requirements for long-term repository disposal; a significant amount of the radiation and decay heat in fission product waste comes from Cs-137 and Sr-90. For the purposes of this project, the Fission Product Extraction (FPEX) process is being considered to be the baseline extraction method. The objective of this project was to evaluate the nature and behavior of candidate materials for cesium and strontium immobilization; this will include assessments with minor additions of yttrium, barium, and rubidium in these materials. More specifically, the proposed research achieved the following objectives (as stated in the original proposal): (1) Synthesize simulated storage ceramics for Cs and Sr using an existing labscale steam reformer at Purdue University. The simulated storage materials will include aluminosilicates, zirconates and other stable ceramics with the potential for high Cs and Sr loading. (2) Characterize the immobilization performance, phase structure, thermal properties and stability of the simulated storage ceramics. The ceramic products will be stable oxide powders and will be characterized to quantify their leach resistance, phase structure, and thermophysical properties. The research progressed in two stages. First, a steam reforming process was used to generate candidate Cs/Sr storage materials for characterization. This portion of the research was carried out at Purdue

  4. Anomalous aryl strengthening of americium and europium complexes during extraction by alkylenediphosphine dioxides from perchloric acid media

    International Nuclear Information System (INIS)

    Extraction of americium and europium from perchlorate environments by solutions of three types of methylenediphosphine dioxides, namely (C6H5)P(O)(CH2)sub(n)(O)P(C6H5)2, (C6H5)2P(O)CH2(O)P(C8H17)2 and (C8H17)2P(O)(CH2)sub(n)(O)P(C8H17)2 has been studied (n is 1 or 2 ) The diluents used have been dichlorethane and chloroform. In perchlorate environments the distribuiton coefficients of americium and europium have proved to be by about 3 orders of magnitude higher than in nitric acid environments, i.e. in perchlorate media the complexes are far more stable. Separation coefficients of americium and REE in perchloric acid soutions are much higher than in nitrate environments. The average value of Am/Eu separation coeffecient at 1-5 M acidity was about 6 (with dichlorethane as diluent) or about 7 (with chloroform as diluent). The complexes essentially exist as trisolvated. Americium complexes display anomalous stability increase upon being diluted: by about 2 orders of magnitude with dichlorethane and by up to 3 orders of magnitude with chloroform used as diluent

  5. Reversible, Selective Trapping of Perchlorate from Water in Record Capacity by a Cationic Metal-Organic Framework.

    Science.gov (United States)

    Colinas, Ian R; Silva, Rachel C; Oliver, Scott R J

    2016-02-16

    We report the capture of ppm-level aqueous perchlorate in record capacity and kinetics via the complete anion exchange of a cationic metal-organic framework. Ambient conditions were used for both the synthesis of silver 4,4'-bipyridine nitrate (SBN) and the exchange, forming silver 4,4'-bipyridine perchlorate (SBP). The exchange was complete within 90 min, and the capacity was 354 mg/g, representing 99% removal. These values are greater than current anion exchangers such as the resins Amberlite IRA-400 (249 mg/g), Purolite A530E (104 mg/g), and layered double hydroxides (28 mg/g). Moreover, unlike resins and layered double hydroxides, SBN is fully reusable and displays 96% regeneration to SBN in nitrate solution, with new crystal formation allowing the indefinite cycling for perchlorate. We show seven cycles as proof of concept. Perchlorate contamination of water represents a serious health threat because it is a thyroid endocrine disruptor. This noncomplexing anionic pollutant is significantly mobile and environmentally persistent. Removal of other anionic pollutants from water such as chromate, pertechnetate, or arsenate may be possible by this methodology. PMID:26765213

  6. Preparation and characterization of cesium-137 aluminosilicate pellets for radioactive source applications

    International Nuclear Information System (INIS)

    Twenty-seven fully loaded 137Cs aluminosilicate pellets were fabricated in a hot cell by the vacuum hot pressing of a cesium carbonate/montmorillonite clay mixture at 15000C and 570 psig. Four pellets were selected for characterization studies which included calorimetric measurements, metallography, scanning electron microscope and electron backscattering (SEM-BSE), electron microprobe, x-ray diffraction, and cesium ion leachability measurements. Each test pellet contained 437 to 450 curies of 137Cs as determined by calorimetric measurements. Metallographic examinations revealed a two-phase system: a primary, granular, gray matrix phase containing large and small pores and small pore agglomerations, and a secondary fused phase interspersed throughout the gray matrix. SEM-BSE analyses showed that cesium and silicon were uniformly distributed throughout both phases of the pellet. This indicated that the cesium-silicon-clay reaction went to completion. Aluminum homogeneity was unconfirmed due to the high background noise associated with the inherent radioactivity of the test specimens. X-ray diffraction analyses of both radioactive and non-radioactive aluminosilicate pellets confirmed the crystal lattice structure to be pollucite. Cesium ion quasistatic leachability measurements determined the leach rates of fully loaded 137Cs sectioned pollucite pellets to date to be 4.61 to 34.4 x 10-10 kg m-2s-1, while static leach tests performed on unsectioned fully loaded pellets showed the leach rates of the cesium ion to date to be 2.25 to 3.41 x 10-12 kg m-2s-1. The cesium ion diffusion coefficients through the pollucite pellet were calculated using Fick's first and second laws of diffusion. The diffusion coefficients calculated for three tracer level 137Cs aluminosilicate pellets were 1.29 x 10-16m2s-1, 6.88 x 10-17m2s-1, and 1.35 x 10-17m2s-1, respectively

  7. The crystal structures of potassium and cesium trivanadates

    Science.gov (United States)

    Evans, H.T.; Block, S.

    1966-01-01

    Potassium and cesium trivanadates are monoclinic and isomorphous, space group P21/m, with the following dimensions (Z = 2): KV3O8, a = 7.640 A, b = 8.380 A, c = 4.979 A, ??= 96?? 57???; CsV3O8, a = 8.176 A, b = 8.519 A, c = 4.988 A, ?? = 95?? 32???. The crystal structure of KV3O8 has been determined from hk0, 0kl, and h0l Weissenberg data with an R factor of 0.15. The structure of CsV3O8 has been refined with 1273 hkl Weissenberg data to an R factor of 0.089. The structures consist of corrugated sheets based on a linkage of distorted VO6, octahedra. Two of the vanadium atoms lie in double, square-pyramid groups V2O8, which are linked through opposite basal corners into chains along the b axis. The chains are joined laterally along the c axis into sheets by the third vanadium atom in VO groups, also forming part of a square-pyramid coordination. Various aspects of these structures are compared with other known oxovanadate structures.

  8. ATLAS tile calorimeter cesium calibration control and analysis software

    International Nuclear Information System (INIS)

    An online control system to calibrate and monitor ATLAS Barrel hadronic calorimeter (TileCal) with a movable radioactive source, driven by liquid flow, is described. To read out and control the system an online software has been developed, using ATLAS TDAQ components like DVS (Diagnostic and Verification System) to verify the hardware before running, IS (Information Server) for data and status exchange between networked computers, and other components like DDC (DCS to DAQ Connection), to connect to PVSS-based slow control systems of Tile Calorimeter, high voltage and low voltage. A system of scripting facilities, based on Python language, is used to handle all the calibration and monitoring processes from hardware perspective to final data storage, including various abnormal situations. A QT based graphical user interface to display the status of the calibration system during the cesium source scan is described. The software for analysis of the detector response, using online data, is discussed. Performance of the system and first experience from the ATLAS pit are presented

  9. Cesium sorption and desorption behavior of clay minerals

    International Nuclear Information System (INIS)

    Cesium sorption and desorption of clay minerals (montmorillonite, beidellite, nontronite, weathered biotite, rectorite and illite) were investigated by consecutive sorption-desorption (CSD) experiments. In batch sorption experiment, two solutions with different Cs concentration 10-3 and 10-7 mol/L) were used. In batch desorption experiments, Cs sorbed samples in sorption experiments were treated 5 times with 1 mol/L ammonium acetate solution. In the case of CSD experiments using 10-3 mol/L Cs solution, the exchangeable cations (Na, Ca, and K) in the clay samples affected to the sorption ratio of Cs, and this effect depended on the type of clay mineral. The desorption ratios of untreated, Na-exchanged and Ca-exchanged weathered biotite ranged from 23 to 33%, while that of other samples was over 80%. In the case of CSD experiments using 10-7 mol/L Cs solution, the sorption ratio of montmorillonite was smaller than that of the other clay samples. In desorption experiments, more than 10-9 mol sorbed Cs remained in 1.0 g of the sample after 5 extraction times. These results indicate that all examined clay samples are able to strongly adsorb Cs with a capacity of more than 10-9 mol/g. (author)

  10. Broadband Vibrational Cooling of Cold Cesium Molecules: Theory and Experiments

    Institute of Scientific and Technical Information of China (English)

    D. Sofikitis; A. Fioretti; S. Weber; M. Viteau; A. Chotia; R. Horchani; M. Allegrini; B. Chatel; D. Comparat; P. Pillet

    2009-01-01

    The use of a broadband, frequency shaped femtosecond laser on translationally cold cesium molecules has recently demonstrated to be a very efficient method of cooling also the vibrational degree of freedom. A sample of cold molecules, initially distributed over several vibrational levels, has thus been transfered into a single selected vibrational level of the singlet X1∑g ground electronic state. Our method is based on repeated optical pumping by laser light with a spectrum broad enough to excite all populated vibrational levels but limited in its frequency bandwidth with a spatial light modulator. In such a way we are able to eliminate transitions from the selected level, in which molecules accumulate. In this paper we briefly report the main experimental results and then address, in a detailed way by computer simulations, the perspectives for a "complete" cooling of the molecules, including also the rotational degree of freedom. Since the pumping process strongly depends on the rclative shape of the ground and excited potential curves, ro-vibrational cooling through different excited states is theoretically compared.

  11. Evaluation of a cesium adsorbent grafted with ammonium 12-molybdophosphate

    Science.gov (United States)

    Shibata, Takuya; Seko, Noriaki; Amada, Haruyo; Kasai, Noboru; Saiki, Seiichi; Hoshina, Hiroyuki; Ueki, Yuji

    2016-02-01

    A fibrous cesium (Cs) adsorbent was developed using radiation-induced graft polymerization with a cross-linked structure containing a highly stable adsorption ligand. The ligand, ammonium 12-molybdophosphate (AMP), was successfully introduced onto the fibrous polyethylene trunk material. The resulting Cs adsorbent contained 36% nonwoven fabric polyethylene (NFPE), 1% AMP, 2% triallyl isocyanurate (TAIC) and 61% glycidyl methacrylate (GMA). The adsorbent's Cs adsorption capacity was evaluated using batch and column tests. It was determined that the adsorbent could be used in a wide pH range. The amount of desorbed molybdenum, which can be used as an estimate for AMP stability on the Cs adsorbent, was minimized at the standard drinking water pH range of 5.8-8.6. Based from the inspection on the adherence of these results to the requirements set forth by the Food Sanitation Act by a third party organization, it can be concluded that the developed Cs adsorbent can be safely utilized for drinking water.

  12. Ion exchange performance of commercial crystalline silicotitanates for cesium removal

    Energy Technology Data Exchange (ETDEWEB)

    Braun, R.; Dangieri, T.J.; Fennelly, D.J. [and others

    1996-03-01

    A new class of inorganic ion exchangers called crystalline silicotitanates (CST), invented by researchers at Sandia National Laboratories and Texas A&M University, has been commercialized in a joint Sandia-UOP effort. The original developmental materials exhibited high selectivity for the ion exchange of cesium, strontium, and several other radionuclides from highly alkaline solutions containing molar concentrations of Na{sup +}. The materials also showed excellent chemical and radiation stability. Together, the high selectivity and stability of the CSTs made them excellent candidates for treatment of solutions such as the Hanford tank supernates and other DOE radwastes. Sandia National Laboratories and UOP have teamed under a Cooperative Research and Development Agreement (CRADA) to develop CSTs in the powdered form and in an engineered form suitable for column ion exchange use. A continuous-flow, column ion exchange process is expected to be used to remove Cs and other radionuclides from the Hanford supernatant. The powder material invented by the Sandia and Texas A&M team consists of submicron-size particles. It is not designed for column ion exchange but may be used in other applications.

  13. Hanford Isotope Project strategic business analysis Cesium-137 (Cs-137)

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1995-10-01

    The purpose of this business analysis is to address the beneficial reuse of Cesium 137 (Cs-137) in order to utilize a valuable national asset and possibly save millions of tax dollars. Food irradiation is the front runner application along with other uses. This business analysis supports the objectives of the Department of Energy National Isotope Strategy distributed in August 1994 which describes the DOE plans for the production and distribution of isotope products and services. As part of the Department`s mission as stated in that document. ``The Department of Energy will also continue to produce and distribute other radioisotopes and enriched stable isotopes for medical diagnostics and therapeutics, industrial, agricultural, and other useful applications on a businesslike basis. This is consistent with the goals and objectives of the National Performance Review. The Department will endeavor to look at opportunities for private sector to co-fund or invest in new ventures. Also, the Department will seek to divest from ventures that can more profitably or reliably be operated by the private sector.``

  14. Hanford Isotope Project strategic business analysis Cesium-137 (Cs-137)

    International Nuclear Information System (INIS)

    The purpose of this business analysis is to address the beneficial reuse of Cesium 137 (Cs-137) in order to utilize a valuable national asset and possibly save millions of tax dollars. Food irradiation is the front runner application along with other uses. This business analysis supports the objectives of the Department of Energy National Isotope Strategy distributed in August 1994 which describes the DOE plans for the production and distribution of isotope products and services. As part of the Department's mission as stated in that document. ''The Department of Energy will also continue to produce and distribute other radioisotopes and enriched stable isotopes for medical diagnostics and therapeutics, industrial, agricultural, and other useful applications on a businesslike basis. This is consistent with the goals and objectives of the National Performance Review. The Department will endeavor to look at opportunities for private sector to co-fund or invest in new ventures. Also, the Department will seek to divest from ventures that can more profitably or reliably be operated by the private sector.''

  15. Perchlorate and selected metals in water and soil within Mount Rushmore National Memorial, South Dakota, 2011–15

    Science.gov (United States)

    Hoogestraat, Galen K.; Rowe, Barbara L.

    2016-04-14

    Mount Rushmore National Memorial is located in the east-central part of the Black Hills area of South Dakota and is challenged to provide drinking water to about 3 million annual visitors and year-round park personnel. An environmental concern to water resources within Mount Rushmore National Memorial has been the annual aerial fireworks display at the memorial for the Independence Day holiday during 1998–2009. A major concern of park management is the contamination of groundwater and surface water by perchlorate, which is used as an oxidizing agent in firework displays. A study by the U.S. Geological Survey, in cooperation with the National Park Service, was completed to characterize the occurrence of perchlorate and selected metals (constituents commonly associated with fireworks) in groundwater and surface water within and adjacent to Mount Rushmore National Memorial during 2011–15. Concentrations of perchlorate and metals in 106 water samples (collected from 6 groundwater sites and 14 surface-water sites) and 11 soil samples (collected from 11 soil sites) are reported.Within the Mount Rushmore National Memorial boundary, perchlorate concentrations were greatest in the Lafferty Gulch drainage basin, ranging from less than 0.20 to 38 micrograms per liter (μg/L) in groundwater samples and from 2.2 to 54 μg/L in surface-water samples. Sites within the Starling Gulch drainage basin also had some evidence of perchlorate contamination, with concentrations ranging from 0.61 to 19 μg/L. All groundwater and surface-water samples within the unnamed tributary to Grizzly Bear Creek drainage basin and reference sites outside the park boundary had concentrations less than 0.20 μg/L. Perchlorate concentrations in samples collected at the 200-foot-deep production well (Well 1) ranged from 17 to 38 μg/L with a median of 23 μg/L, whereas perchlorate concentrations in samples from the 500-foot-deep production well (Well 2) ranged from 2.1 to 17 μg/L, with a median of 6

  16. Misinterpretation on the risk of radioactive cesium contained in the disaster wastes

    International Nuclear Information System (INIS)

    Osaka Prefectural Government accepted the disaster wastes contained radioactive cesium after investigation them during one year. I explained the process and discussed about the risk management by people and the self-government body. The environmental pollution by radioactive cesium and Act on Special Measures concerning the Handling of Pollution by Radioactive Materials, the progress of treatment of debris, the concentration of radioactive cesium in debris, the acceptance conditions of debris contained small amount of radioactive cesium, evaluation of effects of radioactive materials in debris on the environment, and citizen's opinion of Osaka prefecture are described. The important investigation area of radioactive contamination on the basis of Act on Special Measures concerning the Handling of Pollution by Radioactive Materials, total amount of waste from Fukushima nuclear accident and debris in Miyagi, Iwate and Fukushima prefecture, the concentration of radioactive cesium in debris in Rikuzentakata and Miyako city as of September, 2011, and cumulative number of citizen's opinion to Osaka are illustrated. (S.Y.)

  17. Local mat-forming cyanobacteria effectively facilitate decontamination of radioactive cesium in rice fields

    International Nuclear Information System (INIS)

    The most effective and widespread method to decontaminate radioactive cesium from the Fukushima Daiichi Nuclear Power Plant Disaster was peeling topsoil. But the method had problems, such as large amounts of discarded soil and large-scale work. In nature, cyanobacteria formed biomats on the ground surface and facilitated peeling topsoil when the biomats dried. The cyanobacteria-facilitating peeling decontamination method utilized these cyanobacterial properties. Cyanobacteria are located all over Japan and 'local' cyanobacteria could be used for decontamination without introducing new species. Utilizing cyanobacteria could decrease the amount of discarded soil to about 30% and downsize the execution-scale to individual locations. Cyanobacterial biomats were easily cultivated, especially in rice fields, by maintaining wet conditions and exposure to 100 - 83% solar radiation. Shading by a thin net was helpful in maintaining an environment suitable for cyanobacteria. Nowadays, to prevent uptake of radioactive cesium into rice, K+ is usually added to fertilizer in rice fields. The K+ fertilization in rice fields might also enhance cyanobacterial capture of radioactive cesium, because high concentrations of K+ enhanced cyanobacterial uptake of Cs+. Cyanobacteria could also mitigate the risk of radioactive cesium moving away from a decontaminating rice field. Therefore, the cyanobacteria-facilitating peeling decontamination method was proposed as an easy and safe 'D.I.Y.' method for both farmers and the environment. Besides, plowing rice fields with water before peeling improved the efficiency of this method, because plowing increased the radioactive cesium concentration in the topsoil. (author)

  18. Development program for magnetically assisted chemical separation: Evaluation of cesium removal from Hanford tank supernatant

    International Nuclear Information System (INIS)

    Magnetic particles (MAG*SEPSM) coated with various absorbents were evaluated for the separation and recovery of low concentrations of cesium from nuclear waste solutions. The MAG*SEPSM particles were coated with (1) clinoptilolite, (2) transylvanian volcanic tuff, (3) resorcinol formaldehyde, and (4) crystalline silico-titanate, and then were contacted with a Hanford supernatant simulant. Particles coated with the crystalline silico-titanate were identified by Bradtec as having the highest capacity for cesium removal under the conditions tested (variation of pH, ionic strength, cesium concentration, and absorbent/solution ratio). The MAG*SEPSM particles coated with resorcinol formaldehyde had high distribution ratios values and could also be used to remove cesium from Hanford supernant simulant. Gamma irradiation studies were performed on the MAG*SEPSM particles with a gamma dose equivalent to 100 cycles of use. This irradiation decreased the loading capacity and distribution ratios for the particles by greater than 75%. The particles demonstrated high sensitivity to radiolytic damage due to the degradation of the polymeric regions. These results were supported by optical microscopy measurements. Overall, use of magnetic particles for cesium separation under nuclear waste conditions was found to be marginally effective

  19. Efficiency of fly ash belite cement and zeolite matrices for immobilizing cesium.

    Science.gov (United States)

    Goñi, S; Guerrero, A; Lorenzo, M P

    2006-10-11

    The efficiency of innovative matrices for immobilizing cesium is presented in this work. The matrix formulation included the use of fly ash belite cement (FABC-2-W) and gismondine-type Na-P1 zeolite, both of which are synthesized from fly ash of coal combustion. The efficiency for immobilizing cesium is evaluated from the leaching test ANSI/ANS 16.1-1986 at the temperature of 40 degrees C, from which the apparent diffusion coefficient of cesium is obtained. Matrices with 100% of FABC-2-W are used as a reference. The integrity of matrices is evaluated by porosity and pore-size distribution from mercury intrusion porosimetry, X-ray diffraction and nitrogen adsorption analyses. Both matrices can be classified as good solidify systems for cesium, specially the FABC-2-W/zeolite matrix in which the replacement of 50% of belite cement by the gismondine-type Na-P1 zeolite caused a decrease of two orders of magnitude of cesium mean Effective Diffusion Coefficient (D(e)) (2.8e-09 cm(2)/s versus 2.2e-07 cm(2)/s, for FABC-2-W/zeolite and FABC-2-W matrices, respectively). PMID:16759800

  20. Preparation of Modified Kaolin Filler with Cesium and Its Application in Security Paper

    Directory of Open Access Journals (Sweden)

    Houssni El-Saied

    2013-01-01

    Full Text Available In this study, cesium was added intentionally during paper manufacture for protecting the papers against forgery and counterfeiting by sorbing cesium ions (Cs+ on kaolin, used as special filler in papermaking. The sorption of cesium from aqueous solution by kaolin was studied as a function of pH, shaking time, cesium initial concentration, and mass of kaolin using batch technique. The results showed that a solution containing 10 mg/L Cs+ and 250 mg of kaolin at pH 6 can be used to modify the kaolin. Paper handsheets were prepared containing various percentages of the modified kaolin. The mechanical and optical properties of paper handsheets were studied. The prepared paper handsheets were irradiated by gamma irradiation using different doses. Fourier transform infrared (FTIR spectroscopy was used to study the effect of kaolin modification by cesium and gamma irradiation on paper handsheets properties. The results indicated that modified kaolin enhanced the mechanical and optical properties of paper handsheets. Electron spin resonance (ESR spectroscopy and laser-induced breakdown spectroscopy (LIBS were also used. They provided rapid, sensitive and nondestructive techniques in differentiating between different questioned documents. This study presents a new concept in manufacturing security papers and anticounterfeiting applications.

  1. Cesium-137 in soil texture fractions and its impact on Cesium-137 soil-to-plant transfer

    International Nuclear Information System (INIS)

    Field studies at two sites contaminated by the Chernobyl fallout showed 137Cesium (Cs) soil-to-plant transfer factors in wheat, rye and potato. Transfer values ranged from 0.0017 (potato tuber) to 0.07 (wheat straw). Generally transfer coefficients in cereal grains and potato tubers were significantly below the values of the shoots. A comparison of the two sites led to the conclusion that for all plants investigated 137Cs transfer factors were higher in Lower Austria (Calcic Chernozem) than in Upper Austria (Eutric Cambisol). The specific activities of the texture fractions of the two soil types increased from sand to silt and clay. In the Calcic Chernozem the ratio of the 137Cs activity in the silt fraction to the total activity in the soil was considerably higher than in the Eutric Cambisol. At the same time extractability of 137Cs from the silt fraction of the latter soil was clearly lower. Both results mainly were attributed to the differences between the soils according to the organic matter content of the silt fractions, the Calcic Chernozem being seven times higher. Therefore, the differences in the 137Cs-soil-to-plant transfer can be attributed partly to these soil characteristics. (authors)

  2. Effect of Triethanolamine and Benzaldehyde on the Storage Stability of Polystyrene- Ammonium Perchlorate Propellant

    Directory of Open Access Journals (Sweden)

    K. Kishore

    1986-10-01

    Full Text Available The effect of triethanolamine and benzaldehyde on the stability of polystyrene has been studied by dynamic thermogravimetry (TG. Slower decomposition of polymer in the presence of these compounds indicates their inhibiting ability on the oxidation of the polymer. The burning rate measurements of polystyrene (PS/ammonium perchlorate (AP propellants at ambient temperature and pressure shows an increase with the storage time. The percentage change in the burning rate of the propellants containing aldehyde and amine is less during the ageing which indicates the increased stability of the propellants. The safe-life time of the propellants for the ballistic stability has been calculated from the activation energy for the ageing process using an Arrhenius type equation. The safe-life of the propellants containing triethanolamine and benzaldehyde is more than the neat propellant.

  3. Thyroid scintigraphy and perchlorate discharge test in the diagnosis of congenital hypothyroidism

    Energy Technology Data Exchange (ETDEWEB)

    El-Desouki, M. [Dept. of Medicine, King Saud Univ., Riyadh (Saudi Arabia); Al-Jurayyan, N. [Dept. of Paediatrics, King Saud Univ., Riyadh (Saudi Arabia); Al-Nuaim, A. [Div. of Endocrinology, King Saud Univ., Riyadh (Saudi Arabia); Al-Herbish, A. [Dept. of Paediatrics, King Saud Univ., Riyadh (Saudi Arabia); Abo-Bakr, A. [Dept. of Paediatrics, King Saud Univ., Riyadh (Saudi Arabia); Al-Mazrou, Y. [Ministry of Health, Riyadh (Saudi Arabia); Al-Swailem, A. [Ministry of Health, Riyadh (Saudi Arabia)

    1995-09-01

    Quantitative thyroid scanning using low doses of technetium-99m sodium pertechnetate was performed on 147 infants (55 males and 92 females) with congenital hypothyroidism detected through the national neonatal screening programme. Thirty-two (21.8%) were athyrotic, while 62 (42.2%) had an ectopic thyroid and 53 (36%) had a eutopic gland with increased {sup 99m}Tc uptake (mean 17%; range, 5%-38%). The perchlorate discharge test (PDT) was performed in nine of the infants with ectopic glands and 15 with eutopic glands; the findings were consistent with an organification defect in 22 cases (seven ectopic and 15 eutopic). Thyroid scintigraphy and PDT can add useful aetiological, genetic and prognostic information in the clinical evaluation of infants with congenital hypothyroidism detected by neonatal screening. (orig.). With 4 figs., 1 tab.

  4. Large Angular Jump Mechanism Observed for Hydrogen Bond Exchange in Aqueous Perchlorate Solution

    Energy Technology Data Exchange (ETDEWEB)

    Ji, Minbiao; /SLAC, PULSE /Stanford U., Phys. Dept.; Odelius3, Michael; /Stockholm U.; Gaffney1, K.J.; /aff SLAC, PULSE

    2010-06-11

    The mechanism for hydrogen bond (H-bond) switching in solution has remained subject to debate despite extensive experimental and theoretical studies. We have applied polarization-selective multidimensional vibrational spectroscopy to investigate the H-bond exchange mechanism in aqueous NaClO{sub 4} solution. The results show that a water molecule shifts its donated H-bonds between water and perchlorate acceptors by means of large, prompt angular rotation. Using a jump-exchange kinetic model, we extract an average jump angle of 49 {+-} 4{sup o}, in qualitative agreement with the jump angle observed in molecular dynamics simulations of the same aqueous NaClO{sub 4} solution.

  5. Effect of hydrogen storage alloy on combustion properties of ammonium perchlorate /glycidylazide polymer -based propellant

    Science.gov (United States)

    Li, G. P.; Dou, Y. M.; Chai, C. P.; Luo, Y. J.

    2015-12-01

    Hydrogen storage alloys can serve as good potential fuels for propellant design, by improving the energy and combustion properties. The influence of hydrogen storage alloy (A30) on the combustion properties of ammonium perchlorate/glycidylazide polymer (AP/GAP)-based on propellant were studied. The results showed that A30 could increase the burning rate of propellants by 29.75% and 74.78%, compared with B30 and Al. The combustion model of AP/GAP-based propellant containing different fuel was built. Firstly, A30 reduced the high decomposition temperature and promote condensed phase reaction heat of AP. Secondly, A30 deduced the burning surface temperature. Thirdly, A30 might prove the explosive heat of propellant. Therefore, A30 could greatly improve combustion properties of AP/GAP-based propellant.

  6. Effect of Microwave Heating on the Leaching of Lateritic Nickel Ore in Perchloric Acid

    International Nuclear Information System (INIS)

    In this study, the leaching conditions of Sivrihisar (Adatepe) limonite type lateritic ore in acidic medium were investigated. Leaching experiments were carried out using conventional and microwave-assisted method. The effects of stirring speed, leaching temperature, perchloric acid concentration, solid/liquid ratio and particle size on conventional leaching were determined. Microwave-assisted leaching was carried out by using the optimum results of the conventional leaching. The pre-heating process was applied on different microwave powers (0, 90, 180, 360 and 600 W) and pre-processing time (0, 1, 3, 5, 7, 10, 15 and 20 min). These experimental results demonstrated that acid leaching was a convenient method for Ni extraction from lateritic ore. The higher dissolution and the higher Ni recoveries in the microwave-assisted leaching process were obtained in less leach time. (author)

  7. Thyroid scintigraphy and perchlorate discharge test in the diagnosis of congenital hypothyroidism

    International Nuclear Information System (INIS)

    Quantitative thyroid scanning using low doses of technetium-99m sodium pertechnetate was performed on 147 infants (55 males and 92 females) with congenital hypothyroidism detected through the national neonatal screening programme. Thirty-two (21.8%) were athyrotic, while 62 (42.2%) had an ectopic thyroid and 53 (36%) had a eutopic gland with increased 99mTc uptake (mean 17%; range, 5%-38%). The perchlorate discharge test (PDT) was performed in nine of the infants with ectopic glands and 15 with eutopic glands; the findings were consistent with an organification defect in 22 cases (seven ectopic and 15 eutopic). Thyroid scintigraphy and PDT can add useful aetiological, genetic and prognostic information in the clinical evaluation of infants with congenital hypothyroidism detected by neonatal screening. (orig.). With 4 figs., 1 tab

  8. Potentiometric Electronic Tongue to Resolve Mixtures of Sulfide and Perchlorate Anions

    Directory of Open Access Journals (Sweden)

    Deivy Wilson

    2011-03-01

    Full Text Available This work describes the use of an array of potentiometric sensors and an artificial neural network response model to determine perchlorate and sulfide ions in polluted waters, by what is known as an electronic tongue. Sensors used have been all-solid-state PVC membrane selective electrodes, where their ionophores were different metal-phtalocyanine complexes with specific and anion generic responses. The study case illustrates the potential use of electronic tongues in the quantification of mixtures when interfering effects need to be counterbalanced: relative errors in determination of individual ions can be decreased typically from 25% to less than 5%, if compared to the use of a single proposed ion-selective electrode.

  9. Hydration of some trivalent metal ions extracted as perchlorates with trioctylphosphine oxide in hexane

    International Nuclear Information System (INIS)

    Perchlorates of Sc3+, Y3+, La3+, and Eu3+ have each been extracted from 0.1 mol x dem-3 aqueous solution of μ=1 with trioctylphosphine oxide (TOPO) in hexane. The hydration number of the extracted salts has been determined by Karl Fischer titration. Sc3+, Y3+, and Eu3+ are extracted as the tetra- and hexa-solvates of TOPO but the assumption of octa-solvate on addition to the tetra-solvate explains the extraction data of La3+ well. The hydration number of tetra-solvates is 2(Sc3+ and Eu3+), 3(Y3+) and probably 4 for La3+ ion. That of hexa-and octa-solvates is 4-5. (author)

  10. Hydration and Solvation of Metal Perchlorates Extracted with Trioctylphosphine Oxide in Hexane

    International Nuclear Information System (INIS)

    Perchlorates of Sc3+, Y3+, La3+, and Eu3+ have each been extracted from 0.1 mol dm-3 aqueous solution of μ=1 with trioctylphosphine oxide (TOPO) in hexane. The hydration number of the extracted salts has been determined by Karl Fischer titration. Sc3+, Y3+, and Eu3+ are extracted as the tetra- and hexa-solvates of TOPO but the assumption of octa-solvate on addition to the tetra-solvate explains the extraction data of La3+ well. The hydration number of tetra-solvates is 2 (Sc3+ and Eu3+), 3 (Y3+) and probably 4 for La3+ ion. That of hexa-and octa- solvates is 4-5. (author). 1 tabs

  11. A Consideration for Design of Ammonium Perchlorate/Hydroxyl Terminated Polybutadiene Composite Propellant

    Science.gov (United States)

    Kohga, Makoto

    Specific impulse and burning rate characteristics are the important properties for the propellant design. Because of the requirements for the preparation of ammonium perchlorate (AP)/hydroxyl-terminated polybutadiene (HTPB) composite propellant, there is an upper limit content, φ of AP contained propellant. Specific impulse and burning rate increase with increasing the AP content. The specific impulse, Ispφ and the burning rate, rφ of the propellant prepared at φ, rφ are the highest values of the propellant prepared with AP used as an oxidizer. It is necessary for the propellant design to estimate φ, Ispφ and rφ. The φ, Ispφ and rφ are closely associated with the specific surface area, Swp measured by air-permeability method. Therefore, these values are estimated with Swp. A process for the design of AP/HTPB composite propellant would be proposed in this study.

  12. Complexes of rare-earth perchlorates with ditbutyl amides of di, tri and tetraglycolic acids

    OpenAIRE

    Premlatha, C; Soundararajan, S

    1981-01-01

    New complexes of lanthanide perchlorates with di-t-butyl amides of di, tri and tetraglycolic acids have been synthesised. The complexes have the general formula Ln(DiGA)3(ClO4)3; Ln(TriGA)2 (ClO4)3 and Ln(TetGA)2 (C1O4)3, where Ln = La-Yb and Y and DiGA = N,N′, di-t-butyl diglycolamide, TriGA N,N′, di-t-butyl triglycolamide and TetGA = N,N′ di-t-butyl tetraglycolamide, respectively. The complexes have been characterized by analysis, electrolytic conductance, infrared,1H and13C nuclear magneti...

  13. Sympathetic cooling in a rubidium cesium mixture: Production of ultracold cesium atoms; Sympathetisches Kuehlen in einer Rubidium-Caesium-Mischung: Erzeugung ultrakalter Caesiumatome

    Energy Technology Data Exchange (ETDEWEB)

    Haas, M.

    2007-07-01

    This thesis presents experiments for the production of ultracold rubidium cesium mixture in a magnetic trap. The long-termed aim of the experiment is the study of the interaction of few cesium atoms with a Bose-Einstein condensate of rubidium atoms. Especially by controlled variation of the cesium atom number the transition in the description of the interaction by concepts of the one-particle physics to the description by concepts of the many-particle physics shall be studied. The rubidium atoms are trapped in a magneto-optical trap (MOT) and from there reloaded into a magnetic trap. In this the rubidium atoms are stored in the state vertical stroke f=2,m{sub f}=2 right angle of the electronic ground state and evaporatively cooled by means of microwave-induced transitions into the state vertical stroke f=1,m{sub f}=1] (microwave cooling). The cesium atoms are also trppaed in a MOT and into the same magnetic trap reloaded, in which they are stored in the state vertical stroke f=4,m{sub f}=4 right angle of the electronic ground state together with rubidium. Because of the different hyperfine splitting only rubidium is evaporatively cooled, while cesium is cooled jointly sympathetically - i.e. by theramal contact via elastic collisions with rubidium atoms. The first two chapters contain a description of interatomic interactions in ultracold gases as well as a short summary of theoretical concepts in the description of Bose-Einstein condensates. The chapters 3 and 4 contain a short presentation of the methods applied in the experiment for the production of ultracold gases as well as the experimental arrangement; especially in the framework of this thesis a new coil system has been designed, which offers in view of future experiments additionally optical access for an optical trap. Additionally the fourth chapter contains an extensive description of the experimental cycle, which is applied in order to store rubidium and cesium atoms together into the magnetic trap. The

  14. Comparison of organic and inorganic ion exchange materials for removal of cesium and strontium from tank waste

    Energy Technology Data Exchange (ETDEWEB)

    Brown, G. [Pacific Northwest National Lab., Richland, WA (United States)

    1996-10-01

    This work is part of an ESP task to develop high-capacity, selective, solid extractants for cesium, strontium, and technetium from nuclear wastes. Pacific Northwest National Laboratory (PNNL) staff are investigating novel ion exchangers for use in nuclear waste remediation (groundwater, high-level waste (HLW), and low-level waste (LLW)). Waste components targeted for remediation include cesium, strontium, and technetium.

  15. Application of Probabilistic Risk Assessment in Establishing Perchlorate and Goitrogen Risk Mitigation Strategies.

    Science.gov (United States)

    Crawford-Brown, Douglas

    2015-09-01

    This paper applies probabilistic risk assessment in quantifying risks from cumulative and aggregate risk pathways for selected goitrogens in water and food. Results show that the percentages of individuals with a Hazard Index (HI) value above 1 ranges between 30% and 50% both with and without serum half-life correction when a traditional regulatory assessment approach based on establishment of a No Observed Effects Level (NOEL) is used. When an exposure-response curve is instead used and a threshold of 50% inhibition is assumed, 1.1% or less of the population exceeds an HI value of 1 with no serum half-life correction, rising to as high as 11% when serum half-life correction is applied. If 0% to 5% threshold for iodide uptake inhibition is assumed for production of adverse effects, the percentage of the population with an HI above 1 is 46.2% or less with no serum half-life correction, and 47.2% or less when serum half-life correction is applied. The probabilistic analysis shows that while there are exposed groups for whom perchlorate exposures are the primary cause of individuals having HI values above 1, these constitute significantly less than 1% of the population. Instead, the potential risk from exposure to goitrogens is dominated by nitrates without serum half-life correction and thiocyanates with serum half-life correction, suggesting public health protection is better accomplished by a focus on these and other goitrogens expect in highly limited cases where waterborne perchlorate is at unusually high concentrations. PMID:26322488

  16. Behavior of ruthenium, cesium and antimony during simulated HLLW vitrification

    International Nuclear Information System (INIS)

    The behavior of ruthenium, cesium, and antimony during the vitrification of simulated high-level radioactive liquid wastes (HLLW) in a liquid fed melter was studied on a laboratory scale and on a semi-pilot scale. In the laboratory melter of a 2.5 kg capacity, a series of tests with the simulate traced with 103Ru, 134Cs and 124Sb, has shown that the Ru and Cs losses to the melter effluent are generally higher than 10% whereas the antimony losses remain lower than 0.4%. A wet purification system comprising in series, a dust scrubber, a condenser, an ejector venturi and an NOx washing column retains most of the activity present in the off-gas so that the release fractions for Ru at the absolute filter inlet ranges between 5.10-3 to 5.10-5% of the Ru fed, for Cs the corresponding release fraction ranges between 3.10-3 to 10-4% and for Sb the release fraction ranges between 1.7 10-4 to 1.7 10-5%. The same experiments were performed at a throughput of 1 to 2 1 h-1 of simulated solution in the semi-pilot scale unit RUFUS. The RUFUS unit comprises a glass melter with a 50 kg molten glass capacity and the wet purification train comprises in series a dust scrubber, a condenser, an ejector venturi and an NOx washing column. The tracer tests were restricted to 103Ru and 134Cs since the laboratory tests had shown that the antimony losses were very low. The results of the tests are presented

  17. Cesium and Strontium Specific Exchangers for Nuclear Waste Effluent Remediation

    International Nuclear Information System (INIS)

    During the past 50 years, nuclear defense activities have produced large quantities of nuclear waste that now require safe and permanent disposal. The general procedure to be implemented involves the removal of cesium and strontium from the waste solutions for disposal in permanently vitrified media. This requires highly selective sorbents or ion exchangers. Further, at the high radiation doses present in the solution, organic exchangers or sequestrants are likely to decompose over time. Inorganic ion exchangers are resistant to radiation damage and can exhibit remarkably high selectivities. We have synthesized three families of tunnel-type ion exchangers. The crystal structures of these compounds as well as their protonated phases, coupled with ion exchange titrations, were determined and this information was used to develop an understanding of their ion exchange behavior. The ion exchange selectivities of these phases could be regulated by isomorphous replacement of the framework metals by larger or smaller radius metals. In the realm of layered compounds, we prepared alumina, silica, and zirconia pillared clays and sodium micas. The pillared clays yielded very high Kd values for Cs+ and were very effective in removing Cs+ from groundwaters. The sodium micas also had a high affinity for Cs+ but an even greater attraction for S42+. They also possess the property of trapping these ions permanently as the layers slowly decrease their interlayer distance as loading occurs. Sodium nonatitanate exhibited extremely high Kd values for Sr2+ in alkaline tank wastes and should be considered for removal of Sr2+ in such cases. For tank wastes containing complexing agents, we have found that adding Ca2+ to the solution releases the complexed Sr2+ which may then be removed with the CST exchanger

  18. Immobilisation and solidification of cesium on 11 A calcium silicate hydroxy hydrate column

    International Nuclear Information System (INIS)

    Calcium silicate hydrate closely resembling silicate mineral 11 A tobermorite has been synthesised by hydrothermal treatment of lime and silica at 175 degC. The synthetic mineral exhibits selectivity for Cs+ in the presence of strong solutions of alkali and alkaline earth cations, viz, Na+, K+, Mg2+, Ca2+, Sr2+, etc. The Al-substituted form of this mineral effectively separates cesium ion when used as an exchanger in column of size 35x5 mm (hxr). It is possible to remove 98.65±0.5%Cs+ from a mixed solution of cesium and sodium (0.0001N Cs+ + 0.5N Na+). Column separation of cesium from simulated intermediate level waste solution shows that from the first run ∼ 76% Cs+ can be immobilised on a small column, 18x10mm (hxr), having 2.0 g of exchanger. (author)

  19. Studies of cesium and strontium migration in unconsolidated Canadian geological materials

    International Nuclear Information System (INIS)

    Distribution coefficients (Ksub(d)) were measured for cesium and strontium in 16 samples of Canadian unconsolidated geological materials. The samples were collected to cover a wide range of grain size, clay-mineral composition, cation exchange capacity and carbonate mineral content. Distribution coefficients ranged between 102 and 2.0 x 104 ml/g for cesium and between 2.5 and 102 ml/g for strontium, indicating that most unconsolidated geological materials have a substantial ability to retard the migration of cesium, while strontium could generally be expected to be somewhat more mobile. The measured K values were not significantly correlated with the measured soil properties, but appeared to be significantly affected by the background concentration of stable isotopes of the respective radionuclides

  20. The effects of using Cesium-137 teletherapy sources as a radiological weapon (dirty bomb)

    CERN Document Server

    Liolios, Theodore

    2009-01-01

    While radioactive sources used in medical diagnosis do not pose a great security risk due to their low level of radioactivity, therapeutic sources are extremely radioactive and can presumably be used as a radiological weapon. Cobalt-60 and Cesium-137 sources are the most common ones used in radiotherapy with over 10,000 of such sources currently in use worldwide, especially in the developing world, which cannot afford modern accelerators. The present study uses computer simulations to investigate the effects of using Cesium-137 sources from teletherapy devices as a radiological weapon. Assuming a worst-case terrorist attack scenario, we estimate the ensuing cancer mortality, land contamination, evacuation area, as well as the relevant evacuation, decontamination, and health costs in the framework of the linear risk model. The results indicate that an attack with a Cesium-137 dirty bomb in a large metropolitan city (especially one that would involve several teletherapy sources) although would not cause any sta...

  1. Phosphate ceramic solidification and stabilization of cesium-containing crystalline silicotitanate resins.

    Energy Technology Data Exchange (ETDEWEB)

    Langton, C. A.

    1999-05-11

    This paper reports on the fabrication and testing of magnesium potassium phosphate (MKP)-bonded cesium-loaded crystalline silicotitanate (CST) resins. Typical waste loading of CST resins in the final waste forms was 50 wt.%. Physical and chemical characterization of the MKP materials has shown them to be physically, chemically, and mineralogically stable. Long-term durability studies (using the AN 16.1 standard test) showed a leachability index of {approx}18 for cesium in the phosphate matrix when exposed to deionized water under ambient and elevated temperatures. Leaching of cesium was somewhat higher than in glass waste forms as per PCT and MCC-1 tests. MKP-based final waste forms showed no significant weight changes after exposure to aqueous media for {approx}90 days, indicating the highly insoluble nature of the phosphate matrix. In addition, durability of the CST-MKP waste forms was further established by freeze-thaw cycling tests.

  2. Determining Reactor Flux from Xenon-136 and Cesium-135 in Spent Fuel

    CERN Document Server

    Hayes, A C

    2012-01-01

    The ability to infer the reactor flux from spent fuel or seized fissile material would enhance the tools of nuclear forensics and nuclear nonproliferation significantly. We show that reactor flux can be inferred from the ratios of xenon-136 to xenon-134 and cesium-135 to cesium-137. If the average flux of a reactor is known, the flux inferred from measurements of spent fuel could help determine whether that spent fuel was loaded as a blanket or close to the mid-plane of the reactor. The cesium ratio also provides information on reactor shutdowns during the irradiation of fuel, which could prove valuable for identifying the reactor in question through comparisons with satellite reactor heat monitoring data. We derive analytic expressions for these correlations and compare them to experimental data and to detailed reactor burn simulations. The enrichment of the original uranium fuel affects the correlations by up to 3 percent, but only at high flux.

  3. Reduction of cesium levels in the diet through management of food

    International Nuclear Information System (INIS)

    Several processes influence the radionuclide concentration of food products during processing: dilution, losses, concentration. Boiling of leaf vegetables yields a decontamination effect of up to 80% in the case of radioiodine. Peeling of potato tubers results in a reduction of the cesium concentration of 30%. The cesium and strontium concentration of flour is a factor of two lower as compared to the corresponding cereal grain due to the milling process. Significant discrimination occurs during the milk processing. The skimmed milk is significantly richer in cesium, iodine and especially in strontium than the cream. It follows that butter is depleted in its radionuclide contents as compared to other milk produce. Strontium is concentrated in the casein. Pressurized cooking in combination with salting or a treatment with acetic acid results in an Cs-activity loss of beef, veal and lamb meat of 50 to 90%. (Author) 3 figs., 7 tabs., 13 refs

  4. Continuous Separation of Cesium Based on NiHCF/PTCF Electrode by Electrochemically Switched Ion Exchange

    Institute of Scientific and Technical Information of China (English)

    孙斌; 郝晓刚; 王忠德; 张忠林; 刘世斌; 官国清

    2012-01-01

    Nickel hexacyanoferrate (NiHCF) film was synthesized on porous three-dimensional carbon felt (PTCF) substrate by repetitious batch chemical depositions, and the NiHCF/PTCF electrode was used as electrochemically switched ion exchange (ESIX) electrode in a packed bed for continuous separation for cesium ions. The morphologies of the prepared electrodes were characterized by scanning electron microscopy and the effects of solution concentration on the ion-exchange capacity of the electrodes were investigated by cyclic voltammetry technique. Cycling stability and long-term storage stability of NiHCF/PTCF electrodes were also studied. The NiHCF/PTCF electrodes with excellent ion-exchange ability were used to assemble a diaphragm-isolated ESIX reactor for cesium separation. Continuous separation of cesium and regeneration of NiHCF/PTCF electrode based on the diaphragm-isolated reactor were performed in a laboratory-scale two-electrode system.

  5. METHOD 332.0: DETERMINATION OF PERCHLORATE IN DRINKING WATER BY ION CHROMATOGRAPHY WITH SUPPRESSED CONDUCTIVITY AND ELECTROSPRAY IONIZATION MASS SPECTROMETRY

    Science.gov (United States)

    This method is applicable to the identification and quantitation of perchlorate in raw and finished drinking waters. The approach used is ion chromatography with suppressed conductivity and electrospray ionization mass spectrometry (IC-ESI/MS)

  6. Small-Column Cesium Ion Exchange Elution Testing of Spherical Resorcinol-Formaldehyde

    Energy Technology Data Exchange (ETDEWEB)

    Brown, Garrett N.; Russell, Renee L.; Peterson, Reid A.

    2011-10-21

    This report summarizes the work performed to evaluate multiple, cesium loading, and elution cycles for small columns containing SRF resin using a simple, high-level waste (HLW) simulant. Cesium ion exchange loading and elution curves were generated for a nominal 5 M Na, 2.4E-05 M Cs, 0.115 M Al loading solution traced with 134Cs followed by elution with variable HNO3 (0.02, 0.07, 0.15, 0.23, and 0.28 M) containing variable CsNO3 (5.0E-09, 5.0E-08, and 5.0E-07 M) and traced with 137Cs. The ion exchange system consisted of a pump, tubing, process solutions, and a single, small ({approx}15.7 mL) bed of SRF resin with a water-jacketed column for temperature-control. The columns were loaded with approximately 250 bed volumes (BVs) of feed solution at 45 C and at 1.5 to 12 BV per hour (0.15 to 1.2 cm/min). The columns were then eluted with 29+ BVs of HNO3 processed at 25 C and at 1.4 BV/h. The two independent tracers allowed analysis of the on-column cesium interaction between the loading and elution solutions. The objective of these tests was to improve the correlation between the spent resin cesium content and cesium leached out of the resin in subsequent loading cycles (cesium leakage) to help establish acid strength and purity requirements.

  7. Cesium removal from high-pH, high-salt wastwater using crystalline silicotitanate sorbent

    Energy Technology Data Exchange (ETDEWEB)

    Walker, J.F. Jr.; Taylor, P.A.; Lee, D.D.

    1997-11-01

    Treatment and disposal options for Department of Energy (DOE) underground storage tank waste at Hanford, Savannah River, and Oak Ridge National Laboratory (ORNL) are limited by high gamma radiation fields that are produced by high concentrations of cesium in the waste. Treatment methods are needed to remove the cesium from the liquid waste and thus concentrate the cesium into high-activity, remote-handled waste forms. The treated liquids could then be processed and disposed of by more cost-effective means with less radiation exposure to workers. A full-scale demonstration of one cesium removal technology is currently being conducted at ORNL. This demonstration utilizes a modular, mobile ion-exchange system and existing facilities for the off-gas system, secondary containment, and utilities. The ion-exchange material, crystalline silicotitanate (CST), was chosen on the basis of its effectiveness in laboratory tests. The CST, which was developed through a Cooperative Research and Development Agreement between DOE and private industry, has several advantages over current organic ion-exchange technologies. These advantages include (1) the ability to remove cesium in the presence of high concentrations of potassium, (2) a high affinity for cesium in both alkaline and acidic conditions, (3) physical stability over wide alkaline and acidic ranges, and (4) the elimination of large volumes of secondary waste required for regeneration of organic ion exchangers. Approximately 100,000 L of wastewater will be processed during the demonstration. The wastewater being processed has a high salt content, about 4 M NaNO{sub 3}, and a pH of 12 to 13. This paper discusses the results of the full-scale demonstration and compares these results with data from the laboratory tests.

  8. Novel miniaturized sensors for potentiometric batch and flow-injection analysis (FIA) of perchlorate in fireworks and propellants.

    Science.gov (United States)

    Almeer, Saeed H M A; Zogby, Ibrahim A; Hassan, Saad S M

    2014-11-01

    Three planar miniaturized perchlorate membrane sensors (3×5 mm(2)) are prepared using a flexible Kaptan substrate coated with nitron-perchlorate (NT-ClO4) [sensor 1], methylene blue-perchlorate (MB-ClO4) [sensor II] and indium-porphyrin (In-Por) [sensor III] as electroactive materials in PVC membranes plasticized with 2-NPPE. Sensors I, II and III display near-Nernstian response for 1.0×10(-5)-1.0×10(-2), 3.1×10(-5)-1.0×10(-2) and 3.1×10(-6)-1.0×10(-2) mol L(-1) ClO4(-) with lower detection limits of 6.1×10(-6), 6.9×10(-6) and 1.2×10(-6) mol L(-1), and anionic calibration slopes of 50.9±0.4, 48.4±0.4 and 57.7±0.3 mV decade(-1), respectively. Methods for determining perchlorate using these sensors offer many attractive advantages including simplicity, flexibility, cost effectiveness, wide linear dynamic response range (0.1-1000 ppm), low detection limit (sensors show high selectivity in the presence of some inorganic ions (e.g., PO4(3-), SO4(2-), S2O3(2-), NO2(-), NO3(-), N3(-), CN(-), Cl(-), Br(-), I(-)) and automation feasibility. Indium-porphyrin based membrane sensor (sensor III) is used as a detector in a wall-jet flow injection set-up to enable accurate flow injection analysis (FIA) of perchlorate in some fireworks without interferences from the associated reducing agents (sulfur and charcoal), binders (dextrin, lactose), coloring agents (calcium, strontium, copper, iron, sodium), color brighten (linseed oil) and regulators (aluminum flakes) which are commonly used in the formulations. The sensor is also used for perchlorate assessment in some propellant powders. The results fairly agree with data obtained by ion-chromatography.

  9. Separation of cesium from simulated active waste using zinc hexacyanoferrate supported composite

    International Nuclear Information System (INIS)

    Potassium zinc hexacyanoferrate (KZnHCF) was prepared and supported on polyacrylonitrile (PAN) binding polymer. This composite was characterized and used to study the elimination of cesium from acidic radioactive waste containing Sr(II), Eu(II), Am(II), Zr(IV), Hf(IV) and Nb(V) using batch and column techniques. The sorption capacity of this composite for cesium was found to be 1.14 meq/g for column technique. The effect of presence of NH4SCN, NaNo3 and other complexing agents in the aqueous solutions was studied

  10. A preliminary deposit model for lithium-cesium-tantalum (LCT) pegmatites

    Science.gov (United States)

    Bradley, Dwight; McCauley, Andrew

    2013-01-01

    This report is part of an effort by the U.S. Geological Survey to update existing mineral deposit models and to develop new ones. We emphasize practical aspects of pegmatite geology that might directly or indirectly help in exploration for lithium-cesium-tantalum (LCT) pegmatites, or for assessing regions for pegmatite-related mineral resource potential. These deposits are an important link in the world’s supply chain of rare and strategic elements, accounting for about one-third of world lithium production, most of the tantalum, and all of the cesium.

  11. Heat Transfer During Evaporation of Cesium From Graphite Surface in an Argon Environment

    Directory of Open Access Journals (Sweden)

    Bespala Evgeny

    2016-01-01

    Full Text Available The article focuses on discussion of problem of graphite radioactive waste formation and accumulation. It is shown that irradiated nuclear graphite being inalienable part of uranium-graphite reactor may contain fission and activation products. Much attention is given to the process of formation of radioactive cesium on the graphite element surface. It is described a process of plasma decontamination of irradiated graphite in inert argon atmosphere. Quasi-one mathematical model is offered, it describes heat transfer process in graphite-cesium-argon system. Article shows results of calculation of temperature field inside the unit cell. Authors determined the factors which influence on temperature change.

  12. Synthesis of novel calixcrown derivatives with selective complexation towards cesium ions

    Institute of Scientific and Technical Information of China (English)

    Lu Zhang; Juan Du; Li Hua Yuan; Dong Zhang; Gui Ping Dan; Yuan You Yang; Wen Feng

    2011-01-01

    A series of novel calix [4]arenecrown-6 derivatives with an alkenyl loop of various sizes 5-8 were synthesized via intramolecular ring closing olefin metathesis and characterized by 1H NMR, 13C NMR and ESI-HRMS. Their complexation property towards cesium ion was studied by 'H NMR technique. Two-phase extraction of alkali metal ions using UV-vis spectroscopy revealed remarkably different extractabilities. These results indicate that the complexation capacities towards cesium ions can be tuned and controlled through cooperative regulation of the strain of the loop and conformational change of calixcrown skelton.

  13. Measurement of Ionization Threshold of Ultracold Cesium Rydberg Atoms in Static Electric Field

    Institute of Scientific and Technical Information of China (English)

    FENG Zhi-Gang; ZHANG Lin-Jie; ZHAO Jian-Ming; LI Chang-Yong; LI An-Ling; JIA Suo-Tang

    2008-01-01

    We investigate the field ionization spectra of ultracold cesium Rydberg atoms in dc electric field. The ionization thresholds of different electric fields are measured and shift of the ionization threshold relative to field-free ionization threshold is accurately described by (6.06±0.14) F1/2, which is in good agreement with the classical saddle-point model for field ionization. We obtain the field-free ionization threshold of cesium (6P,3/2) as 19674.89士2.99cm-1 by fitting experimental data.

  14. A direct frequency comb for two-photon transition spectroscopy in a cesium vapor

    Institute of Scientific and Technical Information of China (English)

    Zhang Yi-Chi; Wu Ji-Zhou; Li Yu-Qing; Jin Li; Ma Jie; Wang Li-Rong; Zhao Yan-Ting; Xiao Lian-Tuan; Jia Suo-Tang

    2012-01-01

    A phase-stabilized femtosecond frequency comb is used to measure high-resolution spectra of two-photon transition 62S1/2-62P1/2,3/2-82S1/2 in a cesium vapor.The broadband laser output from a femtosecond frequency comb is split into counter-propagating parts,shaped in an original way,and focused into a room-temperature cesium vapor.We obtain high-resolution two-photon spectroscopy by scanning the repetition rate of femtosecond frequency comb,and through absolute frequency measurements.

  15. Recent progress in optically-pumped cesium beam clock at Peking University

    Science.gov (United States)

    Liu, C.; Zhou, S.; Wan, J.; Wang, S.; Wang, Y.

    2016-06-01

    A compact, long-life, and low-drift cesium beam clock is investigated at Peking University, where the atoms are magnetic-state selected and optically detected. Stability close to that of the best commercial cesium clocks has been achieved from 10 to 105 s. As previously shown, the short-term stability is determined by atomic shot noise or laser frequency noise. The stabilizations of microwave power and C-field improve the long-term stability, with the help of a digital servo system based on field-programmable gate array.

  16. Separation of cesium from rad waste solutions with hexacyanoferrate(II) resins of copper and cobalt

    International Nuclear Information System (INIS)

    The separation of radiocesium from low and intermediate level waste solutions by ion exchange with potassium cobalt hexacyanoferrate(II) and potassium copper-cobalt hexacyanoferrate(II) loaded resins was studied. The distribution coefficient(Kd) of cesium as a function of sodium ion concentration was determined. High batch capacity of these resins with regards to cesium make them ideal sorbents that can be used in once through mode in the treatment of rad waste solutions. (author). 3 refs., 1 fig., 1 tab

  17. Concentration Ratios for Cesium and Strontium in Produce Near Los Alamos

    Energy Technology Data Exchange (ETDEWEB)

    S. Salazar, M.McNaughton, P.R. Fresquez

    2006-03-01

    The ratios of the concentrations of radionuclides in produce (fruits, vegetables, and grains) to the concentrations in the soil have been measured for cesium and strontium at locations near Los Alamos. The Soil, Foodstuffs, and Biota Team of the Meteorology and Air Quality Group of the Los Alamos National Laboratory (LANL) obtained the data at locations within a radius of 50 miles of LANL. The concentration ratios are in good agreement with previous measurements: 0.01 to 0.06 for cesium-137 and 0.1 to 0.5 for strontium-90 (wet-weight basis).

  18. Computational study of organo-cesium complexes and the possibility of lanthanide/actinide ions substitution

    Science.gov (United States)

    Rabanal-León, Walter A.; Martinez-Ariza, Guillermo; Roberts, Sue A.; Hulme, Christopher; Arratia-Pérez, Ramiro

    2015-11-01

    Relativistic DFT calculations suggest that two organo-cesium complexes studied herein afford large HOMO-LUMO gaps of around 2.4 eV with the PBE xc-functional, which accounts for their stability. Energy decomposition studies suggest these two complexes are largely ionic with about 20% covalency. However, when the Cs+ ions are substituted by the isoelectronic La3+ and Th4+, their predicted ionicity decreases significantly. The significant increase in covalence indicates that employing Ugi reaction cascades that afford tetramic acid-based organo-cesium complexes may be extended to La3+ and Th4+ organometallics.

  19. Thermal Diffusivity and Specific Heat Measurements of Titanium Potassium Perchlorate Titanium Subhydride Potassium Perchlorate 9013 Glass 7052 Glass SB-14 Glass and C-4000 Muscovite Mica Using the Flash Technique.

    Energy Technology Data Exchange (ETDEWEB)

    Specht, Paul Elliott; Cooper, Marcia A.

    2015-02-01

    The flash technique was used to measure the thermal diffusivity and specific heat of titanium potassium perchlorate (TKP) ignition powder (33wt% Ti - 67wt% KP) with Ventron sup- plied titanium particles, TKP ignition powder (33wt% Ti - 67wt% KP) with ATK supplied titanium particles, TKP output powder (41wt% Ti - 59wt% KP), and titanium subhydride potassium perchlorate (THKP) (33wt% TiH 1.65 - 67wt% KP) at 25 o C. The influence of density and temperature on the thermal diffusivity and specific heat of TKP with Ventron supplied titanium particles was also investigated. Lastly, the thermal diffusivity and specific heats of 9013 glass, 7052 glass, SB-14 glass, and C-4000 Muscovite mica are presented as a function of temperature up to 300 o C.

  20. Acute and chronic activity of perchlorate and hexavalent chromium contamination on the survival and development of Culex quinquefasciatus Say (Diptera: Culicidae)

    Energy Technology Data Exchange (ETDEWEB)

    Sorensen, Mary A. [Department of Entomology, University of California, Riverside, CA 92521 (United States)]. E-mail: mary.sorensen@email.ucr.edu; Jensen, Peter D. [Department of Entomology, University of California, Riverside, CA 92521 (United States); Walton, William E. [Department of Entomology, University of California, Riverside, CA 92521 (United States); Trumble, John T. [Department of Entomology, University of California, Riverside, CA 92521 (United States)

    2006-12-15

    Effects of water contamination with perchlorate and hexavalent chromium [Cr (VI)] on the mosquito Culex quinquefasciatus were assessed. The chronic (10-day) LC{sub 5}s values for perchlorate and chromium were 74 {+-} 8.0 mg/L and 0.41 {+-} 0.15 mg/L, respectively. Relative Growth Index, a measure of growth and mortality rates in a population, was significantly reduced within 5 days for levels of perchlorate as low as 25 mg/L and for levels of chromium as low as 0.16 mg/L. Neither compound altered wing length of surviving adults. In combination, contaminants were synergistic, causing 14% more mortality than predicted. Acute (24-h) LC{sub 5} values for perchlorate and Cr (VI) were 17,000 {+-} 3200 and 38 {+-} 1.3 mg/L, respectively. Effects on mosquito larvae in contaminated environments are likely to be observed for Cr (VI) but not for perchlorate, which generally does not occur at levels as high as those shown here to affect larval mosquitoes. - While pollution with hexavalent chromium may adversely affect Culex quinquefasciatus larvae, levels of perchlorate currently in the environment will not impact these insects.

  1. Perchlorate and selected metals in water and soil within Mount Rushmore National Memorial, South Dakota, 2011–15

    Science.gov (United States)

    Hoogestraat, Galen K.; Rowe, Barbara L.

    2016-04-14

    Mount Rushmore National Memorial is located in the east-central part of the Black Hills area of South Dakota and is challenged to provide drinking water to about 3 million annual visitors and year-round park personnel. An environmental concern to water resources within Mount Rushmore National Memorial has been the annual aerial fireworks display at the memorial for the Independence Day holiday during 1998–2009. A major concern of park management is the contamination of groundwater and surface water by perchlorate, which is used as an oxidizing agent in firework displays. A study by the U.S. Geological Survey, in cooperation with the National Park Service, was completed to characterize the occurrence of perchlorate and selected metals (constituents commonly associated with fireworks) in groundwater and surface water within and adjacent to Mount Rushmore National Memorial during 2011–15. Concentrations of perchlorate and metals in 106 water samples (collected from 6 groundwater sites and 14 surface-water sites) and 11 soil samples (collected from 11 soil sites) are reported.Within the Mount Rushmore National Memorial boundary, perchlorate concentrations were greatest in the Lafferty Gulch drainage basin, ranging from less than 0.20 to 38 micrograms per liter (μg/L) in groundwater samples and from 2.2 to 54 μg/L in surface-water samples. Sites within the Starling Gulch drainage basin also had some evidence of perchlorate contamination, with concentrations ranging from 0.61 to 19 μg/L. All groundwater and surface-water samples within the unnamed tributary to Grizzly Bear Creek drainage basin and reference sites outside the park boundary had concentrations less than 0.20 μg/L. Perchlorate concentrations in samples collected at the 200-foot-deep production well (Well 1) ranged from 17 to 38 μg/L with a median of 23 μg/L, whereas perchlorate concentrations in samples from the 500-foot-deep production well (Well 2) ranged from 2.1 to 17 μg/L, with a median of 6

  2. Bis(μ-bis{[4-(2-pyridylpyrimidin-2-yl]sulfanyl}methanedisilver(I bis(perchlorate

    Directory of Open Access Journals (Sweden)

    Hai-Bin Zhu

    2010-12-01

    Full Text Available In the macrocyclic centrosymmetric dinuclear complex, [Ag2(C19H14N6S22](ClO42, the AgI atom, bis{[4-(2-pyridylpyrimidin-2-yl]sulfanyl}methane (2-bppt ligand and perchlorate anion each lie on a twofold rotation axis. The 2-bppt ligand chelates two four-coordinated AgI atoms through its two bipyridine-like arms. The O atoms of the perchlorate anion are disordered each over two positions of equal occupancy. Adjacent complex molecules are linked by π–π interactions between the pyridine and pyrimidine rings [centroid–centroid distance = 3.663 (8 Å].

  3. Poly[[tetrakis(μ2-pyrazine N,N′-dioxide-κ2O:O′erbium(III] tris(perchlorate

    Directory of Open Access Journals (Sweden)

    James D. Buchner

    2010-09-01

    Full Text Available The title three-dimensional coordination network, {[Er(C4H4N2O24](ClO43}n, is isostructural to that of other lanthanides. The Er+3 cation lies on a fourfold roto-inversion axis. It is coordinated in a distorted square-antiprismatic fashion by eight O atoms from bridging pyrazine N,N′-dioxide ligands. There are two unique pyrazine N,N′-dioxide ligands. One ring is located around an inversion center, and there is a a twofold rotation axis at the center of the other ring. There are also two unique perchlorate anions. One is centered on a twofold rotation axis and the other on a fourfold roto-inversion axis. The perchlorate anions are located in channels that run perpendicular to (001 and (110 and interact with the coordination network through C—H...O hydrogen bonds.

  4. Vibrational Spectroscopic Study on Ion Solvation and Association of Lithium Perchlorate in 4-Methoxymethyl-ethylene Carbonate

    Institute of Scientific and Technical Information of China (English)

    QIAO,Hong-Wei; LUAN,He-Lin; ZHOU,Zhi-Ming; YAO,Wen

    2007-01-01

    Solvation interaction and ion association in solutions of lithium perchlorate/4-methoxymethyl-ethylene carbonate(MEC)have been studied by using Infrared and Raman spectra as a function of concentration of lithium perchlorate.The splitting of ring deformation band and ring ether asymmetric stretching band,and the change of Carbonyl stretching band suggest that there should be a strong interaction between Li+ and the solvent molecules,and the site of solvation should be the oxygen atom of carbonyl group.The apparent solvation number of Li+ was calculated by using band fitting technique.The solvation number was decreased from 3.3 to 1.1 with increasing the concentration of LiClO4/MEC solutions.On the other hand,the band fitting for the ClO ̄4 band revealed the presence of contact ion pair,and free ClO ̄4 anion in the concentrated solutions.

  5. X-ray imaging performance of structured cesium iodide scintillators.

    Science.gov (United States)

    Zhao, Wei; Ristic, Goran; Rowlands, J A

    2004-09-01

    Columnar structured cesium iodide (CsI) scintillators doped with Thallium (Tl) have been used extensively for indirect x-ray imaging detectors. The purpose of this paper is to develop a methodology for systematic investigation of the inherent imaging performance of CsI as a function of thickness and design type. The results will facilitate the optimization of CsI layer design for different x-ray imaging applications, and allow validation of physical models developed for the light channeling process in columnar CsI layers. CsI samples of different types and thicknesses were obtained from the same manufacturer. They were optimized either for light output (HL) or image resolution (HR), and the thickness ranged between 150 and 600 microns. During experimental measurements, the CsI samples were placed in direct contact with a high resolution CMOS optical sensor with a pixel pitch of 48 microns. The modulation transfer function (MTF), noise power spectrum (NPS), and detective quantum efficiency (DQE) of the detector with different CsI configurations were measured experimentally. The aperture function of the CMOS sensor was determined separately in order to estimate the MTF of CsI alone. We also measured the pulse height distribution of the light output from both the HL and HR CsI at different x-ray energies, from which the x-ray quantum efficiency, Swank factor and x-ray conversion gain were determined. Our results showed that the MTF at 5 cycles/mm for the HR type was 50% higher than for the HL. However, the HR layer produces approximately 36% less light output. The Swank factor below K-edge was 0.91 and 0.93 for the HR and HL types, respectively, thus their DQE(0) were essentially identical. The presampling MTF decreased as a function of thickness L. The universal MTF, i.e., MTF plotted as a function of the product of spatial frequency f and CsI thickness L, increased as a function of L. This indicates that the light channeling process in CsI improved the MTF of

  6. Analysis of perchlorate, thiocyanate, nitrate and iodide in human amniotic fluid using ion chromatography and electrospray tandem mass spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Blount, Benjamin C. [Division of Laboratory Sciences, National Center for Environmental Health, Centers for Disease Control and Prevention, Atlanta, GA 30341 (United States)]. E-mail: bblount@cdc.gov; Valentin-Blasini, Liza [Division of Laboratory Sciences, National Center for Environmental Health, Centers for Disease Control and Prevention, Atlanta, GA 30341 (United States)

    2006-05-10

    Because of health concerns surrounding in utero exposure to perchlorate, we developed a sensitive and selective method for quantifying iodide, as well as perchlorate and other sodium-iodide symporter (NIS) inhibitors in human amniotic fluid using ion chromatography coupled with electrospray ionization tandem mass spectrometry. Iodide and NIS inhibitors were quantified using a stable isotope-labeled internal standards (Cl{sup 18}O{sub 4} {sup -}, S{sup 13}CN{sup -} and {sup 15}NO{sub 3} {sup -} with excellent assay accuracy of 100%, 98%, 99%, 95% for perchlorate, thiocyanate, nitrate and iodide, respectively, in triplicate analysis of spiked amniotic fluid sample). Excellent analytical precision (<5.2% RSD for all analytes) was found when amniotic fluid quality control pools were repetitively analyzed for iodide and NIS-inhibitors. Selective chromatography and tandem mass spectrometry reduced the need for sample cleanup, resulting in a rugged and rapid method capable of routinely analyzing 75 samples/day. Analytical response was linear across the physiologically relevant concentration range for the analytes. Analysis of a set of 48 amniotic fluid samples identified the range and median levels for perchlorate (0.057-0.71, 0.18 {mu}g/L), thiocyanate (<10-5860, 89 {mu}g/L), nitrate (650-8900, 1620 {mu}g/L) and iodide (1.7-170, 8.1 {mu}g/L). This selective, sensitive, and rapid method will help assess exposure of the developing fetus to low levels of NIS-inhibitors and their potential to inhibit thyroid function.

  7. Concentration of zinc ions in perchlorate medium by a menbrane-gel using an acid extractant (DEHPA)

    OpenAIRE

    Belhadji L.; Belkacemi F.; Hadj-Boussaad D.E.

    2013-01-01

    Recent decades, it is an awareness of the importance of ecological balance in the environment, balances threatened by industrial pollution. A new spirit presides we seek to minimize pollution of receiving waters. The present work is to study the liquid-gel-extraction of zinc ions in perchlorate medium by an acid extractant: the di (ethyl-2 hexyl) phosphorique acid, or DEHPA. Two types of polymers were used as supports of solvent extraction: a polybutadiene rubber cross-linked respectively wit...

  8. Reactions between cerium(IV) and methyl-6-x-derivatives of aniline in perchloric acid solutions

    International Nuclear Information System (INIS)

    The oxidation of 2,6-dimethyl-, 2-isopropyl-6-methyl, 2-chloro-6-methyl-and 2-methyl-6-nitro aniline with cerium(IV) in perchloric acid solutions has been examined. It has been found that the concentration of hydrogen ions and the basicity of nitrogen atom in the amine group decide about the resultant intermediate products. Some of these products can be practically prepared using cerium(IV) as an oxidizing agent. (author). 16 refs, 1 tab

  9. Detection of trace organics in Mars analog samples containing perchlorate by laser desorption/ionization mass spectrometry.

    Science.gov (United States)

    Li, Xiang; Danell, Ryan M; Brinckerhoff, William B; Pinnick, Veronica T; van Amerom, Friso; Arevalo, Ricardo D; Getty, Stephanie A; Mahaffy, Paul R; Steininger, Harald; Goesmann, Fred

    2015-02-01

    Evidence from recent Mars missions indicates the presence of perchlorate salts up to 1 wt % level in the near-surface materials. Mixed perchlorates and other oxychlorine species may complicate the detection of organic molecules in bulk martian samples when using pyrolysis techniques. To address this analytical challenge, we report here results of laboratory measurements with laser desorption mass spectrometry, including analyses performed on both commercial and Mars Organic Molecule Analyzer (MOMA) breadboard instruments. We demonstrate that the detection of nonvolatile organics in selected spiked mineral-matrix materials by laser desorption/ionization (LDI) mass spectrometry is not inhibited by the presence of up to 1 wt % perchlorate salt. The organics in the sample are not significantly degraded or combusted in the LDI process, and the parent molecular ion is retained in the mass spectrum. The LDI technique provides distinct potential benefits for the detection of organics in situ on the martian surface and has the potential to aid in the search for signs of life on Mars.

  10. Physical barrier effect of geopolymeric waste form on diffusivity of cesium and strontium.

    Science.gov (United States)

    Jang, J G; Park, S M; Lee, H K

    2016-11-15

    The present study investigates the physical barrier effect of geopolymeric waste form on leaching behavior of cesium and strontium. Fly ash-based geopolymers and slag-blended geopolymers were used as solidification agents. The leaching behavior of cesium and strontium from geopolymers was evaluated in accordance with ANSI/ANS-16.1. The diffusivity of cesium and strontium in a fly ash-based geopolymer was lower than that in Portland cement by a factor of 10(3) and 10(4), respectively, showing significantly improved immobilization performance. The leaching resistance of fly ash-based geopolymer was relatively constant regardless of the type of fly ash. The diffusivity of water-soluble cesium and strontium ions were highly correlated with the critical pore diameter of the binder. The critical pore diameter of the fly ash-based geopolymer was remarkably smaller than those of Portland cement and slag-blended geopolymer; consequently, its ability physically to retard the diffusion of nuclides (physical barrier effect) was superior.

  11. Immobilisation of radio cesium loaded ammonium molybdo phosphate in glass matrices

    International Nuclear Information System (INIS)

    Long half life and easy availability from high level wastes make 137Cesium most economical radiation source. High level liquid waste processing for 137 Cesium removal has become easier due to development of Cesium specific granulated ammonium molybdophosphate (AMP) composite. In such applications, resulting spent composite AMP itself represents high active solid waste and immobilization of these materials in cement may not be acceptable. Studies on immobilization of 137Cs loaded AMP were taken up in order to achieve twin goals of increasing safety and minimizing processing costs of the final matrix. Studies indicated that phosphate modified sodium borosilicate SPNM glasses prepared under usual oxidizing conditions are not suitable for immobilization of 137Cs loaded on AMP .Phosphate glasses containing Na2O, P2O5, B2O3, Fe2O3, Al2O3 and SiO2 as major constituents are capable of incorporating 6 to 8 % AMP. The Normalized Leach rates of these glasses for sodium, cesium, boron and silica are 10-4 to 10-6 gm/cm2/day which are comparable to or better than those reported for NBS glasses incorporating HLW. Homogeneity of the final matrix was confirmed by x-ray diffraction analysis. Further studies on characterization of these glasses would establish their acceptability. (author)

  12. Removal of cesium ions from waste solution using sericite incorporated into nickel hexacyanoferrate

    Energy Technology Data Exchange (ETDEWEB)

    Jeon, Choong; Cha, Ju-Hyun [Gangneung-Wonju National University, Wonju (Korea, Republic of)

    2015-11-15

    To increase adsorption capacity and selectivity for cesium ions from waste solution, sericite was chemically modified by means of nickel hexacyanoferrate (NiHCF) with a high selectivity trap agent for cesium. Scanning electron microscopy (SEM) and energy dispersive X-ray (EDX) spectroscopy were used for the characteristic analysis of surface onto the NiHCF-sericite. The adsorption capacity of cesium ions for the NiHCF-sericite increased about 2.5 times, as compared with natural sericite at initial pH 5.0 of waste solution. Adsorption equilibrium was investigated by Langmuir and Freundlich isotherm model, respectively. Maximum adsorption capacity was estimated as 16.583mg/g, and the Langmuir isotherm fits the adsorption data better than Freundlich model. The adsorption process was determined as an exothermic reaction and all adsorption was completed in 30 min. In addition, the adsorption capacity of cesium ions was not greatly affected by ionic strength (-0.1M NaCl concentration) and other metals in mixed waste solution.

  13. Assessment of commercially available ion exchange materials for cesium removal from highly alkaline wastes

    Energy Technology Data Exchange (ETDEWEB)

    Brooks, K.P.; Kim, A.Y.; Kurath, D.E.

    1996-04-01

    Approximately 61 million gallons of nuclear waste generated in plutonium production, radionuclide removal campaigns, and research and development activities is stored on the Department of Energy`s Hanford Site, near Richland, Washington. Although the pretreatment process and disposal requirements are still being defined, most pretreatment scenarios include removal of cesium from the aqueous streams. In many cases, after cesium is removed, the dissolved salt cakes and supernates can be disposed of as LLW. Ion exchange has been a leading candidate for this separation. Ion exchange systems have the advantage of simplicity of equipment and operation and provide many theoretical stages in a small space. The organic ion exchange material Duolite{trademark} CS-100 has been selected as the baseline exchanger for conceptual design of the Initial Pretreatment Module (IPM). Use of CS-100 was chosen because it is considered a conservative, technologically feasible approach. During FY 96, final resin down-selection will occur for IPM Title 1 design. Alternate ion exchange materials for cesium exchange will be considered at that time. The purpose of this report is to conduct a search for commercially available ion exchange materials which could potentially replace CS-100. This report will provide where possible a comparison of these resin in their ability to remove low concentrations of cesium from highly alkaline solutions. Materials which show promise can be studied further, while less encouraging resins can be eliminated from consideration.

  14. Transfer of radioactive cesium from soil to rape plants, rape blossoms and rape honey

    International Nuclear Information System (INIS)

    Due to the test of atomic weapons and the accident in the nuclear power plant at Chernobyl, the vegetation in Germany has been exposed to cesium contamination in the soil. It was to be expected that activity would migrate from soil to plants and to food products. In this work, the transfer of radioactive cesium from soil to rape plants (Brassica napus var. oleifera), rape blossoms and further to rape honey was investigated. By measuring the gamma activity of cesium using germanium detectors with measuring capacity up to 30 h per sample (limit of detection about 0.14 Bq/kg to 0.19 Bq/kg), we determined a mean transfer factor fcs = 0,116 ± 0,080 for the system soil-rape plant, fcs = 0.065 + 0.075 for the system soil-rape blossom and F!S = 0.098 + 0.044 for the system soil-rape honey (plants and honey wet mass, soil dry mass) (Table IV). Additionally, for the transfer of cesium from rape plants to rape honey, a factor of fcs = 2.04 ± 7.23 (both wet mass) was determined. Due to some environmental circumstances, which can hardly ever be taken into account, the results obtained sometimes differ considerably. Nevertheless, the mean transfer factors are within the range of values found in literature (Table V)

  15. Cesium-137 and americium-241 distribution by granulometric fractions of soil at Azgir test site grounds

    International Nuclear Information System (INIS)

    In measurements of radionuclide specific content in surface soil layer of contaminated territories it is important to determine in what agglomerations of soil particles there is the highest radionuclide concentration. For this purpose granulometric composition of soil at Azgir test site was studied and cesium-137 and americium-241 distribution by soil fractions was researched. (author)

  16. Strontium-90 and cesium-137 in sea fish (from Jun. 1982 to Dec. 1982)

    International Nuclear Information System (INIS)

    Strontium-90 and cesium-137 in sea fish (from Jun. to Dec. 1982) were determined. Fish was collected from 22 sampling locations. Only the edible part was used in case of larger sized fish, and the whole part was used in case of smaller ones. The results are sown in a table. (Namekawa, K.)

  17. Strontium-90 and cesium-137 in sea fish (from Nov. 1982 to Jun. 1983)

    International Nuclear Information System (INIS)

    Strontium-90 and cesium-137 in sea fish (from Nov. 1982 to Jun. 1983) were determined. Fishes were collected from eight sampling locations. Only the edible part was used in case of larger sized fish, and the whole part was used in case of smaller ones. The results are shown in a table. (J.P.N.)

  18. Strontium-90 and cesium-137 in sea fish (from Oct. 1981 to Jun. 1982)

    International Nuclear Information System (INIS)

    Strontium-90 and cesium-137 in sea fishes (from Oct. 1981 to Jun. 1982) were determined. Fish was collected from eight sampling locations. Only the edible part was used in case of larger sized fish, and the whole part was used in case of smaller ones. The results are shown in a table. (Namekawa, K.)

  19. Leachability of cobalt and cesium from natural and chemically treated zeolites

    International Nuclear Information System (INIS)

    The determination of leachability of radioisotopes of cesium and cobalt from preloaded zeolites in distilled water, base solution and acid solution has been studied. For the experiment, we used natural and chemically treated zeolites. The zeolites before leaching were calcined at different temperatures. (author). 8 refs., 5 figs., 2 tabs

  20. Nanophotonic hybridization of narrow atomic cesium resonances and photonic stop gaps of opaline nanostructures

    NARCIS (Netherlands)

    Harding, P.J.; Pinkse, P.W.H.; Mosk, A.P.; Vos, W.L.

    2015-01-01

    We study a hybrid system consisting of a narrow-band atomic optical resonance and the long-range periodic order of an opaline photonic nanostructure. To this end, we have infiltrated atomic cesium vapor in a thin silica opal photonic crystal. With increasing temperature, the frequencies of the opal'

  1. Electromagnetically-induced transparency in a multi-V-type system in cesium atomic vapour

    Institute of Scientific and Technical Information of China (English)

    赵建明; 尹王保; 汪丽蓉; 肖连团; 贾锁堂

    2002-01-01

    Electromagnetically-induced transparency is observed in a three-level multi-V-type system in cesium vapour atroom temperature. The absorption property is measured and the hyperfine structures of atomic states can be determined.The results of the experiment agree with the theoretical analysis.

  2. Dual cesium and rubidium atomic fountain with a 10-16 level accuracy and applications

    International Nuclear Information System (INIS)

    Atomic fountains are the most accomplished development of the atomic clocks based on the cesium atom whose hyperfine resonance defines the SI second since 1967. Today these systems are among those which realize the second with the best accuracy. We present the last developments of the cold cesium and rubidium atom dual fountain experiment at LNE-SYRTE. This unique dual setup would allow to obtain an outstanding resolution in fundamental physics tests based on atomic transition frequency comparisons. In order to enable operation with both atomic species simultaneously, we designed, tested and implemented on the fountain new collimators which combine the laser lights corresponding to each atom. By comparing our rubidium fountain to another cesium fountain over a decade, we performed a test of the stability of the fine structure constant at the level of 5 * 10-16 per year. We carried on the work on the clock accuracy and we focused on the phase gradients effects in the interrogation cavity and on the microwave leakage. The fountain accuracy has been evaluated to 4 * 10-16 for the cesium clock and to 5 * 10-16 for the refurbished rubidium clock. As a powerful instrument of metrology, our fountain was implicated in many clock comparisons and contributed many times to calibrate the International Atomic Time. Furthermore, we used the fountain to perform a new test of Lorentz local invariance. (author)

  3. Separation of cesium-137 from uranium fission products via a NeoflonR column supporting tetraphenylboron

    International Nuclear Information System (INIS)

    Cesium is a member of the Group I alkali metals, very reactive earth metals that react vigorously with both air and water. The chemistry of cesium is much like the chemistry of neighboring elements on the periodic table, potassium and rubidium. This close relation creates many problems in plant-life exposed to cesium because it is so easily confused for potassium, an essential nutrient to plants. Radioactive 134Cs and 137Cs are also chemically akin to potassium and stable cesium. Uptake of these radioactive isotopes from groundwater by plant-life destroys the plant-life and can potentially expose humans to the radioactive affects of 134Cs and 137Cs. Much experimental work has been focused on the separation of 137Cs from uranium fission products. In previous experimental work performed a column consisting of Kel-F supporting tetraphenylboron (TPB) was utilized to separate 137Cs from uranium fission products. It is of interest at this time to attempt the separation of 134Cs from 0.01M EDTA using the same method and Neoflon in the place of Kel-F as the inert support. The results of this experiment give a separation efficiency of 88% and show a linear relationship between the column bed length and the separation efficiency obtained. (author)

  4. Cesium Sorption from Concentrated Acidic Tank Wastes Using Ammonium Molybdophosphate-polyacrylonitrile Composite Sorbents

    Energy Technology Data Exchange (ETDEWEB)

    Todd, Terry Allen; Mann, Nicholas Robert; Tranter, Troy Joseph; Sebesta, F.; John, J.; Motl, A.,

    2002-10-01

    Ammonium molybdophosphate-polyacrylonitrile (AMP-PAN) composite sorbents have been evaluated for the removal of cesium from Idaho National Engineering and Environmental Laboratory (INEEL) concentrated acidic tank waste. Batch contacts were performed to qualitatively evaluate the effects of increased nitric acid, sodium and potassium. An equilibrium isotherm was generated with simulated concentrated tank waste solutions and fit to the Langmuir equation. Additional batch contact experiments were performed to determine if mercury, plutonium and americium would sorb onto AMP-PAN. Dynamic sorption was evaluated in column tests employing 1.5 cm3 columns operating at 5, 10 and 20 bed volumes of flow per hour. Results indicate, as expected, that dynamic cesium sorption capacity is reduced as the flowrate is increased. Calculated dynamic capacities for cesium were 22.5, 19.8 and 19.6 mg Cs/g sorbent, for 5, 10 and 20 bed volume per hour flows, respectively. The thermal stability of loaded AMP-PAN was evaluated by performing thermogrovimetric analysis (TGA) on samples of AMP, PAN (polymer), and AMP-PAN. Results indicate that AMP-PAN is stable to 400 °C, with less than a 10% loss of weight, which is at least partially due to loss of water of hydration. The evaluation of AMP-PAN indicates that it will effectively remove cesium from concentrated acidic tank waste solutions.

  5. Sorption behavior of cesium from aqueous solution on magnetic hexacyanoferrate materials

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Hengxuan; Zhao, Xuan, E-mail: zhxinet@tsinghua.edu.cn; Wei, Jiying; Li, Fuzhi

    2014-08-15

    Highlights: • A novel pathway of synthesizing magnetic hexacyanoferrate material was developed. • The synthesized material can offer a high capacity for sorption of cesium. • The material can offer a fast removal of cesium in kinetic performance. • The fine M-PTH particle can be easily separated from wastewater for recirculation. - Abstract: The rapid development of the nuclear power plant in China leads to increasing attention to the treatment of low-level radioactive wastewater (LLRW). One of possibilities is the application of inorganic adsorbent like potassium titanium hexacyanoferrate (PTH), which can exhibit the effective adsorption of cesium. In this paper, the PTH material was optimized by means of being loaded on magnetite substrate. The synthesized material (magnetic PTH, M-PTH), with a particle size of less than 100 nm, can offer a high capacity and favorable kinetic performance, however, without difficulties of separation from the LLRW due to its magnetic characterizations. The batch experiments demonstrate that cesium sorption isotherm of M-PTH coincide well with Langmuir model. The calculated capacity amounts to 0.517 mmol/g, approximately 1.5 times the capacity of zeolite materials. The sorption process follows the pseudo-second-order sorption model. In the initial phase the rate-controlling step is intraparticle diffusion. With the Cs accumulation on the particle surface, external diffusion performs an important role together with intraparticle diffusion.

  6. Z' indication from new APV data in Cesium and searches at linear colliders

    OpenAIRE

    Casalbuoni, R.; De Curtis, S.; Dominici, D.; Gatto, R.; Riemann, S.

    2000-01-01

    New data on parity violation in atomic cesium can be explained by a new neutral vector boson almost unmixed with Z, with a mass in the TeV range and sizeable couplings to the fermions. The properties of such additional Z' can be investigated at future linear colliders.

  7. Cobalt-60 and cesium-137 for the sterilization of food. Radiation treatment of food

    International Nuclear Information System (INIS)

    The brief article discusses the reasons justifying in the eyes of the authors the irradiation of food with ionizing readiation, the irradiation technique applied using cobalt-60 and cesium-137 as a radiation source, and the possible secondary effects of the method. (VHE)

  8. High-temperature cesium capture using activated kaolinite in the presence of chlorine and volatile heavy metals

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Hee Chul; Kim, Jeoung Guk; Yoo, Jae Hyung; Kim, Joon Hyung [KAERI, Taejon (Korea, Republic of); Yoon, Jong Sung [Chungnam National Univ., Taejon (Korea, Republic of)

    2002-05-01

    This study investigated the use of porous activated kaolin particles in the size range of 300- 400 {mu}m as high-temperature sorbents for cesium capture in the presence of chlorine and/or in the presence of cadmium and lead. Packed bed sorption tests by passing CsCl-carrying flue gas through the packed bed of activated porous kaolin particles were first performed at the temperature range of 973-1173 K and a CsCl partial pressure range of 7.4-11.1 Pa. The observed structural change of the sorbent mineral at the stage of sorption revealed the characteristics of an irreversible chemical reaction as a major cesium capturing mechanism. In the fully saturated kaolin sorbent, Cs{sub 2}O{center_dot}Al{sub 2}O{sub 3}{center_dot}SiO{sub 2} is present as a sorption reaction product, together with much smaller amount of water-soluble cesium species. The increase in sorbent bed temperature resulted in an increase in the rate of sorption, but it had no effect on maximum cesium uptake. In the presence of other condensable gas-phase metal chlorides such as cadmium and lead, cesium was preferentially adsorbed onto tested activated kaolinite, but a half of cesium appeared to be physically-sorbed cesium species, CsCl.

  9. Foliar uptake of cesium, iodine and strontium and their transfer to the edible parts of beans, potatoes and radishes

    Science.gov (United States)

    Oestling, O.; Kopp, P.; Burkart, W.

    Considerable fractions of radionuclide solutions deposited on the surface of the leaves may be transferred to the edible parts of plants. In radishes we observed a transfer of more than 40% of the applied cesium radioisotope within a few days. A rather similar uptake was found for beans and potatoes when harvested a month after application of radioactivity. As much as 60% of the applied cesium-isotope remained in (or on) the potato leaves even 8 days after application. The major part could however be washed off the leaves a few hours after application. When radishes were showered with water within 7 h after the application of activity the uptake was greatly reduced. No competitive effect of potassium chloride for the foliar uptake of cesium was found. A 10 -2 M colloidal suspension of Prussian Blue, a chelating agent for monovalent alkali metals such as potassium, cesium, or other monovalent cations, applied as droplets to the leaves one day prior to application of active cesium was found to strongly inhibit the transfer of cesium to the radish. The transfer of iodine and strontium to the edible parts was found to be negligible (or slower) as compared to cesium. In most cases no detectable amounts of these two nuclides were transfered to the edible parts of the radish after 2-5 weeks.

  10. Ion exchange kinetics of cesium for various reaction designs using crystalline silicotitanate, UOP IONSIV IE-911

    Science.gov (United States)

    Kim, Sung Hyun

    Through collaborative efforts at Texas A&M University and Sandia National Laboratories, a crystalline silicotitanate (CST), which shows extremely high selectivity for radioactive cesium removal in highly concentrated sodium solutions, was synthesized. The effect of hydrogen peroxide on a CST under cesium ion exchange conditions has been investigated. The experimental results with hydrogen peroxide showed that the distribution coefficient of cesium decreased and the tetragonal phase, the major component of CST, slowly dissolved at hydrogen peroxide concentrations greater than 1 M. A simple and novel experimental apparatus for a single-layer ion exchange column was developed to generate experimental data for estimation of the intraparticle effective diffusivity. A mathematical model is presented for estimation of effective diffusivities for a single-layer column of CST granules. The intraparticle effective diffusivity for Cs was estimated as a parameter in the analytical solution. By using the least square method, the effective diffusivities of 1.56 +/- 0.14 x 10-11 m2/s and 0.68 +/- 0.09 x 10-11 m2/s, respectively, were obtained. The difference in the two values was due to the different viscosities of the solutions. A good fit of the experimental data was obtained which supports the use of the homogeneous model for this system. A counter-current ion exchange (CCIX) process was designed to treat nuclear waste at the Savannah River Site. A numerical method based on the orthogonal collocation method was used to simulate the concentration profile of cesium in the CCIX loaded with CST granules. To maximize cesium loading onto the CST and minimize the volume of CST, two design cases of a moving bed, where the fresh CST is pulsed into the column at certain periods or at certain concentration of cesium, were investigated. Simulation results showed that cesium removal behavior in the pilot-scale test of CCIX experiment, where the column length is 22 ft and the CST is pulsed

  11. Preparation and characterization of cesium-137 aluminosilicate pellets for radioactive source applications

    Energy Technology Data Exchange (ETDEWEB)

    Schultz, F.J.; Tompkins, J.A.; Haff, K.W.; Case, F.N.

    1981-07-01

    Twenty-seven fully loaded /sup 137/Cs aluminosilicate pellets were fabricated in a hot cell by the vacuum hot pressing of a cesium carbonate/montmorillonite clay mixture at 1500/sup 0/C and 570 psig. Four pellets were selected for characterization studies which included calorimetric measurements, metallography, scanning electron microscope and electron backscattering (SEM-BSE), electron microprobe, x-ray diffraction, and cesium ion leachability measurements. Each test pellet contained 437 to 450 curies of /sup 137/Cs as determined by calorimetric measurements. Metallographic examinations revealed a two-phase system: a primary, granular, gray matrix phase containing large and small pores and small pore agglomerations, and a secondary fused phase interspersed throughout the gray matrix. SEM-BSE analyses showed that cesium and silicon were uniformly distributed throughout both phases of the pellet. This indicated that the cesium-silicon-clay reaction went to completion. Aluminum homogeneity was unconfirmed due to the high background noise associated with the inherent radioactivity of the test specimens. X-ray diffraction analyses of both radioactive and non-radioactive aluminosilicate pellets confirmed the crystal lattice structure to be pollucite. Cesium ion quasistatic leachability measurements determined the leach rates of fully loaded /sup 137/Cs sectioned pollucite pellets to date to be 4.61 to 34.4 x 10/sup -10/ kg m/sup -2/s/sup -1/, while static leach tests performed on unsectioned fully loaded pellets showed the leach rates of the cesium ion to date to be 2.25 to 3.41 x 10/sup -12/ kg m/sup -2/s/sup -1/. The cesium ion diffusion coefficients through the pollucite pellet were calculated using Fick's first and second laws of diffusion. The diffusion coefficients calculated for three tracer level /sup 137/Cs aluminosilicate pellets were 1.29 x 10/sup -16/m/sup 2/s/sup -1/, 6.88 x 10/sup -17/m/sup 2/s/sup -1/, and 1.35 x 10/sup -17/m/sup 2/s/sup -1

  12. Biosorption of cesium by native and chemically modified biomass of marine algae: introduce the new biosorbents for biotechnology applications

    Energy Technology Data Exchange (ETDEWEB)

    Jalali-Rad, R. [Department of Biotechnology, Nuclear Research Center, Atomic Energy Organization of Iran, Tehran (Iran, Islamic Republic of)]. E-mail: rjalali@aeoi.org.ir; Ghafourian, H. [Department of Biotechnology, Nuclear Research Center, Atomic Energy Organization of Iran, Tehran (Iran, Islamic Republic of); Asef, Y. [Department of Biotechnology, Nuclear Research Center, Atomic Energy Organization of Iran, Tehran (Iran, Islamic Republic of); Dalir, S.T. [Department of Biotechnology, Nuclear Research Center, Atomic Energy Organization of Iran, Tehran (Iran, Islamic Republic of); Sahafipour, M.H. [Department of Biotechnology, Nuclear Research Center, Atomic Energy Organization of Iran, Tehran (Iran, Islamic Republic of); Gharanjik, B.M. [Offshore Fisheries Research Center, Chabahar (Iran, Islamic Republic of)

    2004-12-10

    Biosorption batch experiments were conducted to determine the cesium binding ability of native biomass and chemically modified biosorbents derived from marine algae, namely ferrocyanide algal sorbents type 1 and type 2 (FASs1 and FASs2). The applicability of the Langmuir and Freundlich isotherms for representation of the experimental data was investigated. The cesium sorption performances of the various types of sorbents were compared using the maximum capacities (q{sub max} values) obtained from fitting the Langmuir isotherm to the values calculated from the sorption experiments, which FASs type 1 and type 2 showed better sorption performances for cesium. FASs1 and FASs2 derived from formaldehyde and glutaraldehyde crosslinked Padina australis exhibited lower sorption capacities than those prepared from the non-crosslinked one. Most of the cesium ions were bound to FASs1, derived from Sargassum glaucescens and P. australis, in <2 min and equilibrium reached within the first 30 min of contact. Biosorption of cesium by FASs1 derived from P. australis and Cystoseria indica was constantly occurred at a wide range of pH, between 1 and 10, and the highest removal took place at pH 4. The presence of sodium and potassium at 0.5 and 1 mM did not inhibit cesium biosorption by algae biomass. The maximum cesium uptake was acquired using the large particles of FAS2 originated from S. glaucescens (2-4 mm). Desorption of cesium from the metal-laden FASs1 (from P. australis, S. glaucescens and Dictyota indica) was completely achieved applying 0.5 and 1 M NaOH and KOH, although the cesium sorption capacity of the biosorbents (from C. indica and S. glaucescens) decreased by 46-51% after 9 sorption-desorption cycles.

  13. Thermodynamics of the complexation of ciprofloxacin with calcium and magnesium perchlorate

    International Nuclear Information System (INIS)

    Highlights: → The thermodynamics of the reactions of ciprofloxacin (CIP) with Ca(ClO4)2 and Mg(ClO4)2 were investigated by conductometric titration. → The reactions of CIP with each ion produce two ionic complexes with the formulas M(CIP)2+ and M(CIP)22+. → The change in enthalpy and entropy were negative which indicate that the complexation is driven by the enthalpy change. - Abstract: The thermodynamics of the reactions of ciprofloxacin (CIP) with calcium perchlorate (Ca(ClO4)2) and magnesium perchlorate (Mg(ClO4)2) have been investigated in water-methanol solvent using conductometric titration. The reactions of CIP with each ion produce two ionic complexes with the general formulas M(CIP)2+ and M(CIP)22+. The stability constants K1 and K2 at 25 oC for the complexes formed from the reaction with Ca(ClO4)2 were 8.84 x 104 and 3.62 x 104, respectively. For the reaction with Mg(ClO4)2K1 and K2 were 1.72 x 105 and 2.50 x 103, respectively. The enthalpy (ΔH1, ΔH2, ΔH12) and entropy (ΔS1, ΔS2, ΔS12) of complexation reactions were determined from the temperature dependence of the complexation constants. The reactions of CIP with both ions are accompanied by a decrease in entropy (ΔS12 = -468.12 and -478.89 J/K mol for complexation with Ca(ClO4)2 and Mg(ClO4)2, respectively) and enthalpy (ΔH12 = -193.09 and -192.01 kJ/mol for complexation with Ca(ClO4)2 and Mg(ClO4)2, respectively), which indicate that the reactions are driven by the enthalpy change.

  14. Thermodynamics of the complexation of ciprofloxacin with calcium and magnesium perchlorate

    Energy Technology Data Exchange (ETDEWEB)

    Al-Mustafa, Jamil, E-mail: malkawi@just.edu.jo [Department of Applied Chemistry, Faculty of Arts and Sciences, Jordan University of Science and Technology, P.O. Box 3030, Irbid (Jordan); Taha, Ziyad A. [Department of Applied Chemistry, Faculty of Arts and Sciences, Jordan University of Science and Technology, P.O. Box 3030, Irbid (Jordan)

    2011-07-10

    Highlights: {yields} The thermodynamics of the reactions of ciprofloxacin (CIP) with Ca(ClO{sub 4}){sub 2} and Mg(ClO{sub 4}){sub 2} were investigated by conductometric titration. {yields} The reactions of CIP with each ion produce two ionic complexes with the formulas M(CIP){sup 2+} and M(CIP){sub 2}{sup 2+}. {yields} The change in enthalpy and entropy were negative which indicate that the complexation is driven by the enthalpy change. - Abstract: The thermodynamics of the reactions of ciprofloxacin (CIP) with calcium perchlorate (Ca(ClO{sub 4}){sub 2}) and magnesium perchlorate (Mg(ClO{sub 4}){sub 2}) have been investigated in water-methanol solvent using conductometric titration. The reactions of CIP with each ion produce two ionic complexes with the general formulas M(CIP){sup 2+} and M(CIP){sub 2}{sup 2+}. The stability constants K{sub 1} and K{sub 2} at 25 {sup o}C for the complexes formed from the reaction with Ca(ClO{sub 4}){sub 2} were 8.84 x 10{sup 4} and 3.62 x 10{sup 4}, respectively. For the reaction with Mg(ClO{sub 4}){sub 2}K{sub 1} and K{sub 2} were 1.72 x 10{sup 5} and 2.50 x 10{sup 3}, respectively. The enthalpy ({Delta}H{sub 1}, {Delta}H{sub 2}, {Delta}H{sub 12}) and entropy ({Delta}S{sub 1}, {Delta}S{sub 2}, {Delta}S{sub 12}) of complexation reactions were determined from the temperature dependence of the complexation constants. The reactions of CIP with both ions are accompanied by a decrease in entropy ({Delta}S{sub 12} = -468.12 and -478.89 J/K mol for complexation with Ca(ClO{sub 4}){sub 2} and Mg(ClO{sub 4}){sub 2}, respectively) and enthalpy ({Delta}H{sub 12} = -193.09 and -192.01 kJ/mol for complexation with Ca(ClO{sub 4}){sub 2} and Mg(ClO{sub 4}){sub 2}, respectively), which indicate that the reactions are driven by the enthalpy change.

  15. Spectroscopic study of perchlorates and other oxygen chlorides in a Martian environmental chamber

    Science.gov (United States)

    Wu, Zhongchen; Wang, Alian; Ling, Zongcheng

    2016-10-01

    We report a study where the molecular spectral features of nine anhydrous and hydrous oxygen chlorides were analyzed both under Mars atmospheric pressure and temperature conditions in a Planetary Environment and Analysis Chamber (PEACh) and, for comparison, under ambient laboratory conditions. The goal is to understand the effect of Mars environmental conditions (mainly temperature T and CO2 pressure P) on their spectral features as determined by both Raman and NIR spectroscopy. These results will be used for in situ simultaneous identification of the Cl O4- and other intermediate oxygen chloride products generated during a dynamic electrostatic discharge (ESD) experiment. We have three major findings from the first phase of this study: (1) the ν1 Raman peak position is the most sensitive parameter for identifying the cation speciation in perchlorates (e.g., Na, Mg, Ca), the hydration state of magnesium perchlorate (e.g., Mg(ClO4)2 ṡ xH2O, x = 0 , 2 , 4 , 6), and the degree of oxidation of sodium oxygen chlorides (e.g., NaClOy, y = 1 , 2 , 3 , 4); (2) ν1 Raman peak positions of most tested hydrous and anhydrous oxygen chlorides show no detectable changes within the tested T and P ranges relevant to the environmental conditions at Mars surface and shallow subsurface, but water Raman peaks of the hydrated salts change following T decreases; (3) under the P &T conditions relevant to current surface and shallow subsurface at Mars mid-latitude regions, both Mg(ClO4)2 ṡ 6H2O and Ca(ClO4)2 ṡ 2H2O are stable against dehydration, while NaClO4 ṡ H2O dehydrates, with a dehydration rate that is a function of T which was quantified by in situ NIR spectroscopy. These results are useful for the interpretations of the data from current orbital remote sensing (Vis-NIR spectra) and from future landed missions (Raman spectra). Furthermore, we have designed a set of systematic ESD experiments to be conducted in PEACh for studying the pathways and the rates of oxygen chloride

  16. Anomalous aryl strengthening of complexes at americium and europium extraction with alkylenediphospine dioxide from perchloric media

    International Nuclear Information System (INIS)

    Studied was the extraction of americium(3) and europium(3) from perchlorate solutions(0.001 M) with dioxides of alkylenediphosphines of three types: aryl Ph2P(O)CH2(O)PPh2(briefly 4P), and Ph2P(O)(CH2)2(O)PPh2, mixed Ph2P(O)CH2(O)P(C8H17)2 (or 2Ph2Oct) and alkyl (C8H17)2P(O)CH2(O)P(C8H17)2 (or 4 Oct). Trisolvates of MeS3x(ClO4)3 are predominantly formed but americium disolvates are also present upon dilution with dichloroethane. For 4Ph,2Ph2Oct and 4 Oct the concentration is, respectively, 1015, 2x1014, and 1013; for disolvates by 4 orders of magnitude lower which is, nevertheless, by 2 orders of magnitude higher than for nitric acid solutions. The separation coefficient of β Am/Eu for 4Ph attains 6-8. As in the case of nitrate solutions, an anomalous aryl strengthening of the complexes is observed: an increase in the distribution coefficients and extraction constants in the series of 4 Oct - 2Ph 2 Oct - 4Ph, in spite of the introduction of electronegative aryl substituents into the dioxide molecule, which reduce electron density on oxygen atoms and basicity of dioxides. In contrast to nitric acid solutions, observed is a nonlinear effect of a change in basicity on extraction properties upon dilution with dichloroethane (dioxide of 2Ph2 Oct does not occupy an intermediate position but is close to 4Ph). Upon dilution with chloroform the dependence is linear and anomalous effect rises due to a different nature of interactions of dioxides with chloroform. When the bridge increases up to ethylene, an anomalous strengthening of the complexes disappears. However, the distribution coefficients upon extraction with alkyl dioxide are considerably lower, which can be explained by a stronger extraction of perchloric acid

  17. Removal of toxic ions (chromate, arsenate, and perchlorate) using reverse osmosis, nanofiltration, and ultrafiltration membranes

    KAUST Repository

    Yoon, Jaekyung

    2009-09-01

    Rejection characteristics of chromate, arsenate, and perchlorate were examined for one reverse osmosis (RO, LFC-1), two nanofiltration (NF, ESNA, and MX07), and one ultrafiltration (UF and GM) membranes that are commercially available. A bench-scale cross-flow flat-sheet filtration system was employed to determine the toxic ion rejection and the membrane flux. Both model and natural waters were used to prepare chromate, arsenate, and perchlorate solutions (approximately 100 μg L-1 for each anion) in mixtures in the presence of other salts (KCl, K2SO4, and CaCl2); and at varying pH conditions (4, 6, 8, and 10) and solution conductivities (30, 60, and 115 mS m-1). The rejection of target ions by the membranes increases with increasing solution pH due to the increasingly negative membrane charge with synthetic model waters. Cr(VI), As(V), and ClO4 - rejection follows the order LFC-1 (>90%) > MX07 (25-95%) ≅ ESNA (30-90%) > GM (3-47%) at all pH conditions. In contrast, the rejection of target ions by the membranes decreases with increasing solution conductivity due to the decreasingly negative membrane charge. Cr(VI), As(V), and ClO4 - rejection follows the order CaCl2 < KCl ≅ K2SO4 at constant pH and conductivity conditions for the NF and UF membranes tested. For natural waters the LFC-1 RO membrane with a small pore size (0.34 nm) had a significantly greater rejection for those target anions (>90%) excluding NO3 - (71-74%) than the ESNA NF membrane (11-56%) with a relatively large pore size (0.44 nm), indicating that size exclusion is at least partially responsible for the rejection. The ratio of solute radius (ri,s) to effective membrane pore radius (rp) was employed to compare ion rejection. For all of the ions, the rejection is higher than 70% when the ri,s/rp ratio is greater than 0.4 for the LFC-1 membrane, while for di-valent ions (CrO4 2 -, SO4 2 -, and HAsSO4 2 -) the rejection (38-56%) is fairly proportional to the ri,s/rp ratio (0.32-0.62) for the ESNA

  18. Performance modeling of an integral, self-regulating cesium reservoir for the ATI-TFE

    International Nuclear Information System (INIS)

    This work covers the performance modeling of an integral metal-matrix cesium-graphite reservoir for operation in the Advanced Thermionic Initiative-Thermionic Fuel Element (ATI-TFE) converter configuration. The objectives of this task were to incorporate an intercalated cesium-graphite reservoir for the 3C24Cs→2C36Cs+Cs(g) two phase equilibrium reaction into the emitter lead region of the ATI-TFE. A semi two-dimensional, cylindrical TFE computer model was used to obtain thermal and electrical converter output characteristics for various reservoir locations. The results of this study are distributions for the interelectrode voltage, output current density, and output power density as a function of axial position along the TFE emitter. This analysis was accomplished by identifying an optimum cesium pressure for three representative pins in the ATI ''driverless'' reactor core and determining the corresponding position of the graphite reservoir in the ATI-TFE lead region. The position for placement of the graphite reservoir was determined by performing a first-order heat transfer analysis of the TFE lead region to determine its temperature distribution. The results of this analysis indicate that for the graphite reservoirs investigated the 3C24Cs→2C36Cs+Cs(g) equilibrium reaction reservoir is ideal for placement in the TFE emitter lead region. This reservoir can be directly coupled to the emitter, through conduction, to provide the desired cesium pressure for optimum performance. The cesium pressure corresponding to the optimum converter output performance was found to be 2.18 torr for the ATI core least power TFE, 2.92 torr for the average power TFE, and 4.93 torr for the maximum power TFE

  19. Synthesis of Iron-ferrocyanide functionalized magnetic nanocluster for the removal of cesium

    International Nuclear Information System (INIS)

    In the present study, magnetite nanocluster was synthesized by hydrothermal method, and coated with iron ferrocyanide for the adsorption of cesium in an aqueous solution through simple addition of iron ferrocyanide in acid condition. We describe the morphology, structure, and physical property of these nanoparticles. In addition, their ability to eliminate cesium from water was also evaluated. In this study, we fabricated Iron ferrocyanide immobilized magnetite nanocluster (IFC-MNC) using hydrothermal methods. The CIFC-MNC exhibited easy separation ability from water by an external magnet, and showed a high removal efficiency of cesium in aqueous solutions. Therefore, the IFC-MNC demonstrated good potential for the treatment of water contaminated with radioactive cesium. gnetic nanoadsorbents composed of a magnetic particles core and functional shell, which adsorb the contaminants, has attracted significant attention in environmental remediation owing to their high surface area and unique superparamagnetism. The nuclear accident at the Fukushima Daiichi nuclear power station in 2011 released a huge quantity of radioactive contaminants into the environment. Among these, cesium Cs-137 is the most problematic contaminant due to its long half-life (30.2 years), and high-energy gamma ray (γ-ray) emissions. Among various adsorbents to treat Cs-137 contaminated water, metal ferrocyanides were widely applied to remove the Cs-137 in water. For better separation of metal ferrocyanide from water, recently, our group reported the fabrication of copper ferrocyanide-functionalized magnetic nanoparticles (Cu-FC-EDA-MNPs) using alkoxysilanes, having ethylenediamine (EDA) group, modified Fe3O4 nanoparticles (EDA-MNPs) for the fast and easy magnetic separation of metal ferrocyanide. However, the fabrication method was multistep procedure. Thus, a more simplified fabrication procedure is still desired

  20. An isotope dilution-precipitation process for removing radioactive cesium from wastewater

    Energy Technology Data Exchange (ETDEWEB)

    Rogers, Harold, E-mail: rogers22@llnl.gov [Lawrence Livermore National Laboratory, 7000 East Avenue, Livermore, CA, 94550 (United States); Bowers, John; Gates-Anderson, Dianne [Lawrence Livermore National Laboratory, 7000 East Avenue, Livermore, CA, 94550 (United States)

    2012-12-15

    Highlights: Black-Right-Pointing-Pointer Developed an isotope dilution-precipitation treatment process for Cs-137 contaminated water. Black-Right-Pointing-Pointer Waste seeded with non-radioactive Cs-133 prior to precipitation with sodium tetraphenylborate. Black-Right-Pointing-Pointer Final Cs-137 concentrations below DOE discharge limit of 3.0 Multiplication-Sign 10{sup -6} {mu}Ci/mL can be achieved. Black-Right-Pointing-Pointer Synthetic wastewater, and industrial low level radioactive proof of principle studies completed. - Abstract: A novel isotope dilution-precipitation method has been developed to remove cesium-137 from radioactive wastewater. The process involves adding stable cesium chloride to wastewater in order to raise the total cesium concentration, which then allows both the stable and radioactive cesium ions to be precipitated together using sodium tetraphenylborate. This process was investigated utilizing laboratory solutions to determine stable cesium dose rates, mixing times, effects of pH, and filtration requirements. Once optimized, the process was then tested on synthetic wastewater and aqueous low-level waste. Experiments showed the reaction to be very quick and stable in the pH range tested, 2.5-11.5. The wastewater may need to be filtered using a 0.45-{mu}m filter, though ferric sulfate has been shown to promote coagulation and settling, thereby eliminating the necessity for filtration. This investigation showed that this isotope dilution-precipitation process can remove Cs-37 levels below the U.S. Department of Energy's (DOE) Derived Concentration Standard (DCS) of 3.0 Multiplication-Sign 10{sup -6} {mu}Ci/mL using a single dosage, potentially allowing the wastewater to be discharged directly to sanitary sewers.

  1. Synthesis of Iron-ferrocyanide functionalized magnetic nanocluster for the removal of cesium

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Hee-Man; Jang, Sung-Chan; Lee, Kune Woo; Seo, Bum-Kyoung; Moon, Jei Kwon [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2014-10-15

    In the present study, magnetite nanocluster was synthesized by hydrothermal method, and coated with iron ferrocyanide for the adsorption of cesium in an aqueous solution through simple addition of iron ferrocyanide in acid condition. We describe the morphology, structure, and physical property of these nanoparticles. In addition, their ability to eliminate cesium from water was also evaluated. In this study, we fabricated Iron ferrocyanide immobilized magnetite nanocluster (IFC-MNC) using hydrothermal methods. The CIFC-MNC exhibited easy separation ability from water by an external magnet, and showed a high removal efficiency of cesium in aqueous solutions. Therefore, the IFC-MNC demonstrated good potential for the treatment of water contaminated with radioactive cesium. gnetic nanoadsorbents composed of a magnetic particles core and functional shell, which adsorb the contaminants, has attracted significant attention in environmental remediation owing to their high surface area and unique superparamagnetism. The nuclear accident at the Fukushima Daiichi nuclear power station in 2011 released a huge quantity of radioactive contaminants into the environment. Among these, cesium Cs-137 is the most problematic contaminant due to its long half-life (30.2 years), and high-energy gamma ray (γ-ray) emissions. Among various adsorbents to treat Cs-137 contaminated water, metal ferrocyanides were widely applied to remove the Cs-137 in water. For better separation of metal ferrocyanide from water, recently, our group reported the fabrication of copper ferrocyanide-functionalized magnetic nanoparticles (Cu-FC-EDA-MNPs) using alkoxysilanes, having ethylenediamine (EDA) group, modified Fe{sub 3}O{sub 4} nanoparticles (EDA-MNPs) for the fast and easy magnetic separation of metal ferrocyanide. However, the fabrication method was multistep procedure. Thus, a more simplified fabrication procedure is still desired.

  2. Preparation and use of polymeric materials containing hydrophobic anions and plasticizers for separation of cesium and strontium

    International Nuclear Information System (INIS)

    Preparation and use is described for polymeric materials containing hydrophobic anions and plasticizers for extraction of cesium and strontium. The use of polymeric materials containing plasticizers which are solvents for hydrophobic anions such as derivatives of cobalt dicarbollide or tetraphenylborate which are capable of extracting cesium and strontium ions from aqueous solutions in contact with the polymeric materials, is described. The polymeric material may also include a synergistic agent for a given ion like polyethylene glycol or a crown ether, for removal of radioactive isotopes of cesium and strontium from solutions of diverse composition and, in particular, for solutions containing large excess of sodium nitrate

  3. Immunological detection of small organic molecules in the presence of perchlorates: relevance to the life marker chip and life detection on Mars.

    Science.gov (United States)

    Rix, Catherine S; Sims, Mark R; Cullen, David C

    2011-11-01

    The proposed ExoMars mission, due to launch in 2018, aims to look for evidence of extant and extinct life in martian rocks and regolith. Previous attempts to detect organic molecules of biological or abiotic origin on Mars have been unsuccessful, which may be attributable to destruction of these molecules by perchlorate salts during pyrolysis sample extraction techniques. Organic molecules can also be extracted and measured with solvent-based systems. The ExoMars payload includes the Life Marker Chip (LMC) instrument, capable of detecting biomarker molecules of extant and extinct Earth-like life in liquid extracts of martian samples with an antibody microarray assay. The aim of the work reported here was to investigate whether the presence of perchlorate salts, at levels similar to those at the NASA Phoenix landing site, would compromise the LMC extraction and detection method. To test this, we implemented an LMC-representative sample extraction process with an LMC-representative antibody assay and used these to extract and analyze a model sample that consisted of a Mars analog sample matrix (JSC Mars-1) spiked with a representative organic molecular target (pyrene, an example of abiotic meteoritic infall targets) in the presence of perchlorate salts. We found no significant change in immunoassay function when using pyrene standards with added perchlorate salts. When model samples spiked with perchlorate salts were subjected to an LMC-representative liquid extraction, immunoassays functioned in a liquid extract and detected extracted pyrene. For the same model sample matrix without perchlorate salts, we observed anomalous assay signals that coincided with yellow coloration of the extracts. This unexpected observation is being studied further. This initial study indicates that the presence of perchlorate salts, at levels similar to those detected at the NASA Phoenix landing site, is unlikely to prevent the LMC from extracting and detecting organic molecules from

  4. Microscopic observations of X-ray and gamma-ray induced decomposition of ammonium perchlorate crystals

    Science.gov (United States)

    Herley, P. J.; Levy, P. W.

    1972-01-01

    The X-ray and gamma-ray induced decomposition of ammonium perchlorate was studied by optical, transmission, and scanning electron microscopy. This material is a commonly used oxidizer in solid propellents which could be employed in deep-space probes, and where they will be subjected to a variety of radiations for as long as ten years. In some respects the radiation-induced damage closely resembles the effects produced by thermal decomposition, but in other respects the results differ markedly. Similar radiation and thermal effects include the following: (1) irregular or ill-defined circular etch pits are formed in both cases; (2) approximately the same size pits are produced; (3) the pit density is similar; (4) the c face is considerably more reactive than the m face; and (5) most importantly, many of the etch pits are aligned in crystallographic directions which are the same for thermal or radiolytic decomposition. Thus, dislocations play an important role in the radiolytic decomposition process.

  5. Effect of Surface Microstructure on the Temperature sensitivity of Burning Rate of Ammonium Perchlorate

    Directory of Open Access Journals (Sweden)

    K. Kishore

    1997-04-01

    Full Text Available Considering Vielle's law and the new thermodynamic model which the authors have developed recently the true dependence of temperature sensitivity of burning rate of ammonium perchlorate (AP on pressure is resolved and experimentally verified for bellet burning. The value of decreases with pressure steeply in regime I' (below 20 atm, but gently in regime I (above 20 atm. The value of powder AP has been determined and it is observed that (powder > (pellet, which clearly suggests that of is innuenced by the surface temperature sensitive parameter and hence by the surface/subsurface microstructure. In powder burning, the buoyant lifting of the particles into the gas phase occurs, Which constitutes the so-called 'free board region' (FER extending just above the true surface. Consequent to the decomposition of AP particles in FER, the condensed phase heat release gets curtailed and (powder becomes larger. A general relationship for in terms of density and surface temperature is suggested, which is applicable to both pellet and powder AP.

  6. Combustion Characteristics and Propulsive Performance of Boron/Ammonium Perchlorate Mixtures in Microtubes

    Science.gov (United States)

    Liang, Daolun; Liu, Jianzhong; Zhou, Junhu; Wang, Yang; Yang, Yuxin

    2016-07-01

    A microthruster is used for the operation tracking and posture control of microsatellites. In this work, the combustion characteristics and propulsive performance of a boron/ammonium perchlorate (B/AP) propellant mixture for a microthruster were investigated. Amorphous B and AP were used in different mass ratios to prepare the propellant samples. A laser-ignition solid micropropulsion test system was set up, and a differential scanning calorimeter was used. The solid combustion products of the samples with good performance were collected. Microstructural and component analyses of the combustion products were performed. Various performance parameters, including the combustion temperature, combustion velocity, spectral intensity, ignition delay time, thrust, specific impulse, density specific impulse, and heat flow, changed with the fuel-oxidant ratio. The optimal fuel-oxidant mass ratio of the propellant samples was 40%, with a density specific impulse of 0.474 kg/m2•s and a maximum heat flow of 4.4913 mW/mg. Analysis of the combustion products revealed that the clearance between particles significantly diminished after combustion. During combustion, the AP completely decomposed, and a large amount of H3BO3, B2O3, and HBO2 was generated.

  7. Size and Shape of Ammonium Perchlorate and their Influence on Properties of Composite Propellant

    Directory of Open Access Journals (Sweden)

    Sunil Jain

    2009-05-01

    Full Text Available Most of the composite propellant compositions contain solid loading up to 86 per cent. The main solid ingredients of composite propellant are ammonium perchlorate (AP and aluminium powder. Therefore, it is a must to characterise these to improve processibility and quality of composite propellant. Effect of particle size on propellants slurry viscosity and ballistic parameters are well documented, however, the effect of oxidizer particle shape is not reported. In the present study, different methods for size and shape characterisation are discussed and effect of size and shape of AP on composite propellant properties are studied. The data indicate that as size of AP decreases, propellant slurry viscosity increases and burn rate increases. The particles having higher shape factor provides less endof mix (EOM viscosity of propellant slurry and burn rate. Further, effect of size of ground AP on shape is also investigated. From the data thus obtained, it is inferred that as size of ground AP decreases, shape factor decreases, and particles become more irregular in shape.Defence Science Journal, 2009, 59(3, pp.294-299, DOI:http://dx.doi.org/10.14429/dsj.59.1523

  8. Biomarker expression in lung of rabbit with pulmonary fibrosis induced by ammonium perchlorate.

    Science.gov (United States)

    Wu, Feng-hong; Guo, Hui-xia; Lin, Ming-fang; Chen, Zhi-ze; Zhou, Xuan; Peng, Kai-liang

    2011-04-01

    Ammonium perchlorate (AP), an oxidizer, has been used in solid propellants. Although AP exposure has been suspected as a risk factor for the development of pulmonary fibrosis, data are still inconclusive. To evaluate the pulmonary toxicity and the potential pulmonary fibrosis caused by occupational exposure to this compound, 25 male rabbits were randomly allocated into five groups to receive AP or bleomycin or saline by intratracheal injection. All rabbits were sacrificed and total RNA from the lungs was extracted. Expressions of types I and III collagens, transforming growth factor-β(1) (TGF-β(1)) and tumour necrosis factor-α (TNF-α) messenger RNA (mRNA) were measured by reverse transcription-polymerase chain reaction (RT-PCR). The expressions of type I and III collagen mRNA in low, moderate and high dose AP groups were significantly higher (p < 0.01 or p < 0.05) than that in the saline group. There was also a significant increased level of TGF-β(1) and TNF-α mRNA in the three AP groups compared with saline control group (p < 0.01 or p < 0.05). These results reveal that AP can increase gene expressions of types I, III collagens, TGF-β(1) and TNF-α in lung of rabbits exposed to AP. The overexpression of these biomarkers were considered as effective indicator linking to the development of pulmonary fibrosis and finally demonstrated that AP has potential to induce pulmonary fibrosis.

  9. Ferroelectric Polarization Switching Dynamics and Domain Growth of Triglycine Sulfate and Imidazolium Perchlorate

    KAUST Repository

    Ma, He

    2016-04-10

    The weak bond energy and large anisotropic domain wall energy induce many special characteristics of the domain nucleation, growth, and polarization switch in triglycine sulfate (TGS) and imidazolium perchlorate (IM), two typical molecular ferroelectrics. Their domain nucleation and polarization switch are rather slower than those of conventional oxide ferroelectrics, which may be due to the weaker bond energy of hydrogen bond or van der Waals bond than that of ionic bond. These chemical bonds dominate the elastic energy, with the latter being an important component of domain wall energy and playing an important role in domain nucleation and domain growth. The ratio of anisotropic domain wall energy to Gibbs free energy is large in TGS and IM, which allows a favorable domain shape and a special domain evolution under a certain electric field. Therefore, this study not only sheds light on the physical nature but also indicates the application direction for molecular ferroelectrics. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim

  10. (2,2′-Bipyridine(2-formyl-6-methoxyphenolatonickel(II perchlorate

    Directory of Open Access Journals (Sweden)

    Cui-Juan Wang

    2009-01-01

    Full Text Available In the title compound, [Ni(C8H7O3(C10H8N2]ClO4, the NiII atom is in a slightly distorted square-planar coordination by two N atoms from the 2,2′-bipyridine (bipy ligand and two O atoms from the deprotonated 2-formyl-6-methoxyphenolate (mbd ligand. The bipy ligand is nearly coplanar with the NiII square plane, the Ni atom being only 0.042 (2 Å from the mean plane, whereas the benzaldehyde plane is folded with respect to the square plane, making a dihedral angle of 19.17 (8°. One of the O atoms of the perchlorate anion is involved in a weak interaction with the Ni atom, with an Ni—O distance of 2.5732 (18 Å. The packing is stabilized by weak C—H...O interactions.

  11. Removal of cesium using coconut fiber in raw and modified forms for the treatment of radioactive liquid wastes

    Energy Technology Data Exchange (ETDEWEB)

    Jesus, Nella N.M. de; Nobre, Vanessa B.; Potiens Junior, Ademar J.; Sakata, Solange K., E-mail: sksakata@ipen.br [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil); Di Vitta, Patricia B. [Universidade de Sao Paulo (USP), SP (Brazil). Instituto de Quimica

    2013-07-01

    Sorption is one of the most studied methods to reduce the volume of radioactive waste streams. Cesium-137 is a radioisotope formed by the fission of uranium and it can cause health problems due to its easy assimilation by cells. The aim of this study is to evaluate the potential of coconut fiber in removing cesium from radioactive liquid wastes; this process can help in disposing radioactive waste. The experiments were performed in batch and the particle size of the fiber ranged between 0.30 mm and 0.50 mm. The fiber was treated with hydrogen peroxide in alkaline medium. The following parameters were analyzed: contact time, pH and concentration of cesium ions in aqueous solution. After the experiments the samples were filtered and cesium remaining in solution was quantified by inductively coupled plasma optical emission spectrometry. (author)

  12. Frequency doubling with periodically poled KTiOPO4 at the fundamental wave of cesium D2 transition

    Institute of Scientific and Technical Information of China (English)

    Xiaoling Song; Zhigang Li; Pengfei Zhang; Gang Li; Yuchi Zhang; Junmin Wang; Tiancai Zhang

    2007-01-01

    @@ We report the continuous wave (CW) second harmonic generation (SHG) with a periodically poled KTiOPO4 (PPKTP) pumped by a diode laser at 852.356 nm, which is exactly resonant on the cesium D2 transition.

  13. Application of a composite sorbent based om natural and synthetic zeolites for cesium ion elimination from water solutions

    International Nuclear Information System (INIS)

    The study has been carried out to determine the effect of variations in the content of natural and synthetic zeolites, being the components of the composite sorbent, on the cesium sorption from the water solution

  14. Spin-dependent asymmetry functions in the elastic and inelastic electron-cesium scattering at intermediate energies

    International Nuclear Information System (INIS)

    In this thesis the measurements of the relative differential cross section, the exchange asymmetry, the spin-orbit asymmetry, and the interference asymmetry for the electron scattering on cesium atoms from 4 to 18 eV is described. (HSI)

  15. Cesium-137 in ash from combustion of biofuels. Application of regulations from the Swedish Radiation Safety Authority; Cesium-137 i aska fraan foerbraenning av biobraenslen. Tillaempning av Straalsaekerhetsmyndighetens regler

    Energy Technology Data Exchange (ETDEWEB)

    Sjoeblom, Rolf (Tekedo AB, Nykoeping (SE))

    2009-03-19

    The Swedish Radiation Safety Authority, SSM, has issued an ordinance on ash contaminated with Cesium-137. It implies amongst other things that ash containing 0,5 - 10 kBq/kg Cesium-137 (so-called contaminated ash) can be used for geotechnical purposes provided that the content in a near-by well does not exceed 1 Bq/litre and that the increase in a near-by fish producing recipient does not exceed 0,1 Bq/litre. The initial plan with the presently reported work was to provide a compilation of how the ordinance for Cesium-137 can be applied in practical work. It became evident, however, in the course of the work that issues related to the co-variation between potassium and Cesium needed further investigation. As a result, the present report comprises also a compilation of this extended information search. Cesium-137 is present in ash as a result of the accident in a nuclear power reactor in Chernobyl in 1986 during which material having a very small grain size was spread to a high altitude. A few days later, Cesium-137 was deposited during rains over large parts of Sweden. This activity penetrated to a depth of one or a few decimetres during the course of the subsequent few days and weeks, after which it was partially taken up by plants and spread in the ecosystem. Section 2 has the character of a handbook. It provides basic information on radiation, and also about the ordinance and other material from the SSI. Section 3 comprises compilations of relevant international status of knowledge. This regards how potassium and Cesium behave in soil and ash, and also how spreading of Cesium can be modelled. Cesium behaves similarly to Potassium but with the difference that Cesium is bonded much more strongly to mineral soil and ash. Potassium and Cesium appears in soil in four different forms: dissolved in the pore water, exchangeable, non-exchangeable and as bonded to minerals. The amount dissolved in the pore water is the smallest and that bonded to minerals is the largest

  16. The promotional effects of cesium promoter on higher alcohol synthesis from syngas over cesium-promoted Cu/ZnO/Al2O3 catalysts

    Energy Technology Data Exchange (ETDEWEB)

    Sun, Jie; Cai, Qiuxia; Wan, Yan; Wan, Shaolong; Wang, Li; Lin, Jingdong; Mei, Donghai; Wang, Yong

    2016-09-02

    In this study, the promotional effects of cesium promoter on higher alcohol (C2+OH) synthesis from syngas over Cs-Cu/ZnO/Al2O3 catalysts were investigated using a combined experimental and theoretical density functional theory (DFT) calculation method. In the presence of cesium, the C2+OH productivity increases from 77.1 g•kgcat-1•h-1 to 157.3 g•kgcat-1•h-1 at 583 K due to the enhancement of the initial C–C bond formation. Detailed analysis of chain growth probabilities (CGPs) confirms that initial C–C bond formation is the rate-determining step in the temperature range of 543-583 K. Addition of cesium promoter significantly increases the productivities of 2-methyl-1-propanol, while the CGPs values (C3* to 2-methyl-C3*) is almost unaffected. With the assistance of cesium promoter, the CGPs of the initial C–C bond formation step (C1* to C2*) could be increased from 0.13 to 0.25 at 583 K. DFT calculations indicate that the initial C–C bond formation is mainly contributed by the HCO+HCO coupling reaction over the ZnCu(211) model surface. In the presence of the Cs2O, the stabilities of key reaction intermediates such as HCO and H2CO are enhanced which facilitates both HCO+HCO and HCO+H2CO coupling reaction steps with lower activation barriers over the Cs2O-ZnCu(211) surface. The promotional effects of cesium on the C2+OH productivity are also benefited from the competitive CH+HCO coupling reaction over CH hydrogenation that leads to lower alkane formation. In addition, Bader charge analysis suggests that the presence of cesium ions would facilitate the nucleophilic reaction between HCO and H2CO for initial C–C bond formation. This work was supported by the National Natural Science Foundation of China (No. 91545114 and No. 91545203). We appreciate the joint PhD scholarship support from the China Scholarship Council. The authors would also like to thank the support from Collaborative Innovation Center of Chemistry for Energy Materials (2011-iChEM). DM

  17. Sugar-metal ion interactions: the complicated coordination structures of cesium ion with D-ribose and myo-inositol.

    Science.gov (United States)

    Hu, Haijian; Xue, Junhui; Wen, Xiaodong; Li, Weihong; Zhang, Chao; Yang, Limin; Xu, Yizhuang; Zhao, Guozhong; Bu, Xiaoxia; Liu, Kexin; Chen, Jia'er; Wu, Jinguang

    2013-11-18

    The novel cesium chloride-D-ribose complex (CsCl·C5H10O5; Cs-R) and cesium chloride-myo-inositol complex (CsCl·C6H12O6; Cs-I) have been synthesized and characterized using X-ray diffraction and FTIR, FIR, THz, and Raman spectroscopy. Cs(+) is eight-coordinated to three chloride ions, O1 and O2 from one D-ribose molecule, O1 from another D-ribose molecule, and O4 and O5 from the third D-ribose molecule in Cs-R. For one D-ribose molecule, the oxygen atom O1 in the ring is coordinated to two cesium ions as an oxygen bridge, O2 is cocoordinated with O1 to one of the two cesium ions, and O4 and O5 are coordinated to the third cesium ion, respectively. O3 does not coordinate to metal ions and only takes part in forming hydrogen bonds. One chloride ion is connected to three cesium ions. Thus, a complicated structure of Cs-D-ribose forms. For Cs-I, Cs(+) is 10-coordinated to three chloride ions, O1 and O2 from one myo-inositol molecule, O3 and O4 from another myo-inositol molecule, O5 and O6 from the third myo-inositol molecule, and O6 from the fourth myo-inositol molecule. One metal ion is connected to four ligands, and one myo-inositol is coordinated to four Cs(+) ions, which is also a complicated coordination structure. Crystal structure results, FTIR, FIR, THz, and Raman spectra provide detailed information on the structure and coordination of hydroxyl groups to metal ions in the cesium chloride-D-ribose and cesium chloride-myo-inositol complexes.

  18. Next Generation Extractants for Cesium Separation from High-Level Waste: From Fundamental Concepts to Site Implementation

    Energy Technology Data Exchange (ETDEWEB)

    Moyer, Bruce A; Bazelaire, Eve; Bonnesen, Peter V; Custelcean, Radu; Delmau, Laetitia H; Ditto, Mary E; Engle, Nancy L; Gorbunova, Maryna G; Haverlock, Tamara J; Levitskaia, Taiana G; Bartsch, Richard A; Surowiec, Malgorzata A; Zhou, Hui

    2005-07-06

    This project unites expertise at Oak Ridge National Laboratory (ORNL) and Texas Tech University (TTU, Prof. Richard A. Bartsch) to answer fundamental questions addressing the problem of cesium removal from high-level tank waste. Efforts focus on novel solvent-extraction systems containing calixcrown extractants designed for enhanced cesium binding and release. Exciting results are being obtained in three areas: (1) a new lipophilic cesium extractant with a high solubility in the solvent; (2) new proton-ionizable calixcrowns that both strongly extract cesium and "switch off" when protonated; and (3) an improved solvent system that may be stripped with more than 100-fold greater efficiency. Scientific questions primarily concern how to more effectively reverse extraction, focusing on the use of amino groups and proton-ionizable groups to enable pH-switching. Synthesis is being performed at ORNL (amino calixcrowns) and TTU (proton-ionizable calixcrowns). At ORNL, the extraction behavior is being surveyed to assess the effectiveness of candidate solvent systems, and systematic distribution measurements are under way to obtain a thermodynamic understanding of partitioning and complexation equilibria. Crystal structures obtained at ORNL are revealing the structural details of cesium binding. The overall objective is a significant advance in the predictability and efficiency of cesium extraction from high-level waste in support of potential implementation at U. S. Department of Energy (USDOE) sites.

  19. Next Generation Extractants for Cesium Separation from High-Level Waste: From Fundamental Concepts to Site Implementation

    Energy Technology Data Exchange (ETDEWEB)

    Moyer, Bruce A.; Bazelaire, Eve; Bonnesen, Peter V.; Custelcean, Radu; Delmau, Laetitia H.; Ditto, Mary E.; Engle, Nancy L.; Gorbunova, Maryna G.; Haverlock, Tamara J.; Levitskaia, Tatiana G.; Bartsch, Richard A.; Surowiec, Malgorzata A.; Zhou, Hui

    2005-07-06

    This project unites expertise at Oak Ridge National Laboratory (ORNL) and Texas Tech University (TTU, Prof. Richard A. Bartsch) to answer fundamental questions addressing the problem of cesium removal from high-level tank waste. Efforts focus on novel solvent-extraction systems containing calixcrown extractants designed for enhanced cesium binding and release. Exciting results are being obtained in three areas: (1) a new lipophilic cesium extractant with a high solubility in the solvent; (2) new proton-ionizable calixcrowns that both strongly extract cesium and ''switch off'' when protonated; and (3) an improved solvent system that may be stripped with more than 100-fold greater efficiency. Scientific questions primarily concern how to more effectively reverse extraction, focusing on the use of amino groups and proton-ionizable groups to enable pH-switching. Synthesis is being performed at ORNL (amino calixcrowns) and TTU (proton-ionizable calixcrowns). At ORNL, the extraction behavior is being surveyed to assess the effectiveness of candidate solvent systems, and systematic distribution measurements are under way to obtain a thermodynamic understanding of partitioning and complexation equilibria. Crystal structures obtained at ORNL are revealing the structural details of cesium binding. The overall objective is a significant advance in the predictability and efficiency of cesium extraction from high-level waste in support of potential implementation at U. S. Department of Energy (USDOE) sites.

  20. Experiments and simulations for the dynamics of cesium in negative hydrogen ion sources for ITER N-NBI

    Energy Technology Data Exchange (ETDEWEB)

    Gutser, Raphael

    2010-07-21

    The injection of fast neutral particles (NBI) into a fusion plasma is an important method for plasma heating and current drive. A source for negative deuterium ions delivering an 1 MeV beam that is accelerated to a specific energy and neutralized by a gas target is required for the ITER-NBI. Cesium seeding is required to extract high negative ion current densities from these sources. The optimization of the cesium homogeneity and control are major objectives to achieve the source requirements imposed by ITER. Within the scope of this thesis, the Monte Carlo based numerical transport simulation CsFlow3D was developed, which is the first computer model that is capable of simulating the flux and the accumulation of cesium on the surfaces of negative-ion sources. Basic studies that support the code development were performed at a dedicated experiment at the University of Augsburg. Input parameters of the ad- and desorption of cesium at ion source relevant conditions were taken from systematic measurements with a quartz micro balance, while the injection rate of the cesium oven at the ion source was determined by surface ionization detection. This experimental setup was used for further investigations of the work function of cesium-coated samples during plasma exposure. (orig.)

  1. Experiments and simulations for the dynamics of cesium in negative hydrogen ion sources for ITER N-NBI

    International Nuclear Information System (INIS)

    The injection of fast neutral particles (NBI) into a fusion plasma is an important method for plasma heating and current drive. A source for negative deuterium ions delivering an 1 MeV beam that is accelerated to a specific energy and neutralized by a gas target is required for the ITER-NBI. Cesium seeding is required to extract high negative ion current densities from these sources. The optimization of the cesium homogeneity and control are major objectives to achieve the source requirements imposed by ITER. Within the scope of this thesis, the Monte Carlo based numerical transport simulation CsFlow3D was developed, which is the first computer model that is capable of simulating the flux and the accumulation of cesium on the surfaces of negative-ion sources. Basic studies that support the code development were performed at a dedicated experiment at the University of Augsburg. Input parameters of the ad- and desorption of cesium at ion source relevant conditions were taken from systematic measurements with a quartz micro balance, while the injection rate of the cesium oven at the ion source was determined by surface ionization detection. This experimental setup was used for further investigations of the work function of cesium-coated samples during plasma exposure. (orig.)

  2. The beta strength function structure in \\beta + decay of lutecium, thulium and cesium isotopes

    CERN Document Server

    Alkhazov, G D; Naumov, Yu V; Orlov, S Yu; Vitman, V D

    1981-01-01

    The spectra of total gamma -absorption in the decays of some lutetium, thulium and cesium isotopes have been measured. The probabilities for level population in the decay of the isotopes have been determined. The deduced beta strength functions reveal pronounced structure. Calculations of the strength functions using the Saxon-Woods potential and the residual Gamow-Teller interaction are presented. It is shown that in beta /sup +/ decay of light thulium and cesium isotopes the strength function comprises more than 70% of the Gamow-Teller excitations with mu /sub tau /=+1. This result is the first direct observation of the Gamov-Teller resonance in beta /sup +/ decay of nuclei with T/sub z/>0. (21 refs).

  3. Light storage via coherent population oscillation in a thermal cesium vapor

    CERN Document Server

    de Almeida, A J F; Maynard, M -A; Laupretre, T; Bretenaker, F; Felinto, D; Goldfarb, F; Tabosa, J W R

    2014-01-01

    We report on the storage of light via the phenomenon of Coherent Population Oscillation (CPO) in an atomic cesium vapor at room temperature. In the experiment the optical information of a probe field is stored in the CPO of two ground states of a Lambda three-level system formed by the Zeeman sublevels of the hyperfine transition F = 3 - F' = 2 of cesium D2 line. We show directly that this CPO based memory is very insensitive to stray magnetic field inhomogeneities and presents a lifetime which is mainly limited only by atomic motion. A theoretical simulation of the measured spectra was also developed and is in very good agreement with the experiment.

  4. Leaching Study in Immobilization of Cesium and Cobalt Radionuclides In Fly Ash- Zeolite Cement

    International Nuclear Information System (INIS)

    Fly ash-zeolite cement was synthesized from industrial by-product fly ash obtained from the thermal electric power station. The synthesis process is based on the hydrothermal-calcination-route of the fly ash. The microstructure of fly ash-zeolite cement was characterized by X-ray diffraction, FT infrared spectroscopy and surface area (F-N2). The efficiency of innovative matrices for immobilizing cesium and cobalt radionuclides is presented in this work. The aim of the present study is to investigate the possibility of solidifying 137Cs and 60Co radionuclides in synthetic fly ash zeolite cement. Leaching behavior of the radionuclides have been studied. The leachability index measured indicated that fly ash zeolite cement matrix can be utilized as an efficient material for immobilizing cesium and cobalt radionuclides than portland cement.

  5. Static and dynamic experiments for the retention of cesium in nitrate containing, nitric acid solutions

    International Nuclear Information System (INIS)

    The separation of cesium from medium active waste (MAW) of the Purex-Process by chromatographic methods is demonstrated using the inorganic ion exchanger ammoniummolybdatophosphate (AMP-1). Other inorganic exchangers like ammoniumhexacyanocobaltousferrate (NCFC), zirkoniumphosphate (ZPH) and antimonypentoxid (HAP) have shown for different pH-values a reasonable retention for cesium (NCFC (pH 12) : 35 g Cs/kgNCFC, ZPH(pH 7) : 100 g Cs/kgZPH and HAP (pH 2) : 55 g Cs/kgHAP). But with a high salt loading (300 g/l NaNO3) a loss of capacities occurs which does not allow the use of these exchangers, whereas AMP-1 is useful from a pH of 9 to conc. HNO3 with this high salt loadings with a capacity of 60 g Cs/kg AMP-1. (orig.)

  6. Kelvin probe studies of cesium telluride photocathode for the AWA photoinjector

    Energy Technology Data Exchange (ETDEWEB)

    Velazquez, D.; Wisniewski, E. E.; Yusof, Z.; Harkay, K.; Spentzouris, L.; Terry, J. [Physics Department at Illinois Institute of Technology, Chicago, IL 60616 and High Energy Physics Division at Argonne National Laboratory, Lemont, IL 60439 (United States); High Energy Physics Division at Argonne National Laboratory, Lemont, IL 60439 (United States); Accelerator Science Division at Argonne National Laboratory, Lemont, IL 60439 (United States); Physics Department at Illinois Institute of Technology, Chicago, IL 60616 (United States)

    2012-12-21

    Cesium telluride is an important photocathode as an electron source for particle accelerators. It has a relatively high quantum efficiency (> 1%), is robust in a photoinjector, and long lifetime. This photocathode is fabricated in-house for a new Argonne Wakefield Accelerator (AWA) beamline to produce high charge per bunch ({approx}50 nC) in a long bunch train. We present some results from a study of the work function of cesium telluride photocathode using the Kelvin Probe technique. The study includes an investigation of the correlation between the quantum efficiency and the work function, the effect of photocathode aging, the effect of UV light exposure on the work function, and the evolution of the work function during and after photocathode rejuvenation via heating.

  7. Strontium-90 and cesium-137 in soil from May 1984 to July 1984

    International Nuclear Information System (INIS)

    Strontium-90 and cesium-137 in soil measured throughout Japan from May to July 1984 are given in pCi/kg and mCi/km2. Sampling points are total of 8 from Kawabe-gun (Akita) to Ibasuki-gun (Kagoshima). Collection and pretreatment of samples, preparation of samples for analysis, separation of strontium-90 and cesium-137, determination of stable strontium, calcium and potassium, and counting are described. Soil was collected from the location in the spacious and flat area without past disturbance on the surface. Soil was taken from two layers of different depths, 0 aproximately 5 cm and 5 approximately 20 cm. After the radiochemical separation, the mounted precipitates were counted for activity using low background beta counters normally for 60 minutes. (Mori, K.)

  8. Characterization of cesium uptake mediated by a potassium transport system of bacteria in a soil conditioner

    International Nuclear Information System (INIS)

    We found that bacteria in a commercial soil conditioner sold in Ishinomaki, Miyagi, exhibited concentrative and saturable cesium ion (Cs+) uptake in the natural range of pH and temperature. The concentration of intracellular Cs+ could be condensed at least a few times higher compared with the outside medium of the cells. This uptake appeared to be mediated by a K+ transport system, since Cs+ uptake was dose-dependently inhibited by potassium ion (K+). Eadie-Hofstee plot analysis indicated that the Cs+ uptake involved a single saturable process. The maximum uptake amount (Jmax) was the same in the presence and absence of K+, suggesting that Cs+ and K+ uptakes were competitive with respect to each other. These bacteria might be useful for bioremediation of cesium-contaminated soil. (author)

  9. Low Level Gamma Spectroscopy Measurements of Radium and Cesium in Lucerne (Medicago Sativa)

    Science.gov (United States)

    Fokapić, S.; Bikit, I.; Mrđa, D.; Vesković, M.; Slivka, J.; Mihaljev, Ž.; Ćupić, Ž.

    2007-04-01

    Nineteen years after Chernobyl nuclear accident, activity concentration of 137Cs still could be detected in food and soil samples in Central and Eastern Europe. In this paper radiation levels of radium and cesium in Lucerne will be presented. It is a perennial plant with a deep root system and it is widely grown throughout the world as forage for cattle. The samples of Lucerne were taken from twelve different locations in Vojvodina in the summer period July-September 2004. The samples were specially dried on the air and after that ground, powdered and mineralized by method of dry burning on the temperature of 450°C. Gamma spectrometry measurements of the ash were performed by means of actively shielded germanium detector with maximal background reduction. For cesium 137Cs 10 mBq/kg order of magnitude detection limits were achieved.

  10. Determination of modelling parameter in the fluctuation and migration of Cesium in soils

    International Nuclear Information System (INIS)

    Cesium radionuclide is one of fission products with high level activity and long life, of about 30 years, therefore it is used as an indicator of a fission product released from a nuclear reactor or a radioactive waste storage. The migration process of cesium in soil is influent by physical and chemical properties of soil and environment in which the sorption process occurred. The data of the physical and chemical properties and the radionuclide retardation in such area are needed for the study of mathematical models of radionuclide migration. The experiment has been performed in laboratory by using soils with particle sizes of -4 - 4.48x10-2 cm/second; the longitudinal dispersivity 0.030 - 0.241 cm; the coefficient of longitudinal dispersion was 4.96x10-5 - 7.69x10-3 cm2/second and retardation factor was 2.30 - 3.39

  11. Chemical treatment of aqueous radioactive Cesium-137 waste using Ferri Chloride

    International Nuclear Information System (INIS)

    Ferric Chloride 6H2O was used for treatment of liquid radioactive wastes containing Cesium-137. Various concentration of ferric chloride 6H2O have been added into the waste at different pH and speed of stirrer. The treatment was based on the coagulans-flocculation and coprecipitation mechanisms. The best result of this experiment was achieved by adding 300 ppm of Ferric chloride 6 H2O into liquid waste on following condition the rate Stirrer was 250 rpm. At this condition, it was found that the separation efficiency and the decontamination factor were 83.32 % and 5.99. The activity of decreasing of aqueous radioactive Cesium-137 waste was 2.10 x 10-4 Ci/l to 3.50 x 10-5 Ci/l

  12. Spectroscopic approach for an electron EDM measurement using neutral cesium atoms

    Science.gov (United States)

    Zhu, Kunyan; Solmeyer, Neal; Weiss, David S.

    2012-06-01

    Observation of a permanent electric dipole moment of the electron (eEDM) would imply CP violating effects not contained in the Standard Model. We describe the state preparation and spectroscopy that will be used to measure the eEDM. Cesium atoms are guided into a measurement chamber, where they are laser-cooled and trapped in a pair of parallel one-dimensional optical lattices. The lattices thread three specially coated glass electric field plates. The measurement chamber is surrounded by a four layer magnetic shield inside of which eight magnetic field coils control the bias and gradient magnetic fields. A series of microwave and low frequency magnetic field pulses transfer the atoms into a superposition state that is sensitive to the eEDM signal. A measurement of the eEDM using neutral cesium atoms can obtain an ultimate shot noise limit of 3x10-30 e-cm.

  13. Adsorption of uranium, cesium and strontium onto coconut shell activated carbon

    International Nuclear Information System (INIS)

    The adsorption of uranium (VI), cesium and strontium ions from aqueous solutions onto a commercial activated carbon obtained by physical activation of coconut shell has been studied in batch systems. In particular the adsorption of uranium, studied as a function of contact time and metal ion concentration, followed pseudo-first-order kinetics. Equilibrium adsorption data were fitted by Langmuir and Freundlich isotherm models and the maximum adsorption capacity of the activated carbon resulted to be 55.32 mg/g. The study showed that the considered activated carbon could be successfully used for uranium adsorption from aqueous solutions. Feasibility of cesium and strontium adsorption onto the same activated carbon has been also investigated. Results showed that no affinities with both of these ions exist. (author)

  14. Stark spectra of Rydberg states in atomic cesium in the vicinity of n=18

    Institute of Scientific and Technical Information of China (English)

    Dong Hui-Jie; Wang Ting; Li Chang-Yong; Zhao Jian-Ming; Zhang Lin-Jie

    2013-01-01

    The Stark structures in a cesium atom around n =18 are numerically calculated.The results show that the components of 20D states with a small azimuthal quantum number |m| shift upward a lot,and those with a large |m| shift downward a little within 1100 V/cm.All components of P states shift downward.Experimental work has been performed in ultracold atomic cesium.Atoms initially in 6P3/2 state are excited to high-n Rydberg states by a polarization light perpendicular to the field,and Stark spectra with 丨m丨=1/2,3/2,5/2 are simultaneously observed with a large linewidth for the first time.The observed spectra are analyzed in detail.The relative transition probability is calculated.The experimental results are in good agreement with our numerical computation.

  15. Perchlorate and volatiles of the brine of Lake Vida (Antarctica): Implication for the in situ analysis of Mars sediments

    Science.gov (United States)

    Kenig, Fabien; Chou, Luoth; McKay, Christopher P.; Jackson, W. Andrew; Doran, Peter T.; Murray, Alison E.; Fritsen, Christian H.

    2016-07-01

    The cold (-13.4°C), cryoencapsulated, anoxic, interstitial brine of the >27 m thick ice of Lake Vida (Victoria Valley, Antarctica) contains 49 µg · L-1 of perchlorate and 11 µg · L-1 of chlorate. Lake Vida brine (LVBr) may provide an analog for potential oxychlorine-rich subsurface brine on Mars. LVBr volatiles were analyzed by solid-phase microextraction (SPME) gas chromatography-mass spectrometry (GC-MS) with two different SPME fibers. With the exception of volatile organic sulfur compounds, most other volatiles observed were artifacts produced in the GC injector when the thermal decomposition products of oxychlorines reacted with reduced carbon derived from LVBr and the SPME fiber phases. Analysis of MilliQ water with perchlorate (40 µg · L-1) showed low level of organic artifacts, reflecting carbon limitation. In order to observe sample-derived organic compounds, both in analog samples and on Mars, the molar abundance of reduced carbon in a sample must exceed those of O2 and Cl2 produced during decomposition of oxychlorines. This suggests that the abundance of compounds observed by the Sample Analysis at Mars (SAM) instruments in Sheepbed samples (CB-3, CB5, and CB6) may be controlled by an increase in the reduced-carbon/oxychlorine ratio of these samples. To increase chances of in situ detection of Martian organics during pyrolysis-GC-MS, we propose that the derivatization agents stored on SAM may be used as an external source of reduced carbon, increasing artificially the reduced-carbon to perchlorate ratio during pyrolysis, allowing the expression of more abundant and perhaps more diverse Martian organic matter.

  16. Perchlorate and Volatiles of the Brine of Lake Vida (Antarctica): Implication for the in Situ Analysis of Mars Sediments

    Science.gov (United States)

    Kenig, Fabien; Chou, Luoth; McKay, Christopher P.; Jackson, W. Andrew; Doran, Peter T.; Murray, Alison E.; Fritsen, Christian H.

    2016-01-01

    The cold (-13.4 C), cryoencapsulated, anoxic, interstitial brine of the 27 m-thick ice of Lake Vida (Victoria Valley, Antarctica) contains 49 microgram L-1 of perchlorate and 11 microgram L-1 of chlorate. Lake Vida brine (LVBr) may provide an analog for potential oxychlorine-rich subsurface brine on Mars. LVBr volatiles were analyzed by solid-phase microextraction (SPME) gas chromatography-mass spectrometry (GC-MS) with two different SPME fibers. With the exception of volatile organic sulfur compounds, most other volatiles observed were artifacts produced in the GC injector when the thermal decomposition products of oxychlorines reacted with reduced carbon derived from LVBr and the SPME fiber phases. Analysis of MilliQ water with perchlorate (40 microgram L-1) showed low level of organic artifacts, reflecting carbon limitation. In order to observe sample-derived organic compounds, both in analog samples and on Mars, the molar abundance of reduced carbon in a sample must exceed those of O2 and Cl2 produced during decomposition of oxychlorines. This suggests that the abundance of compounds observed by the Sample Analysis at Mars (SAM) instruments in Sheepbed samples (CB-3, CB5, and CB6) may be controlled by an increase in the reduced-carbon/oxychlorine ratio of these samples. To increase chances of in situ detection of Martian organics during pyrolysis-GC-MS, we propose that the derivatization agents stored on SAM may be used as an external source of reduced carbon, increasing artificially the reduced-carbon to perchlorate ratio during pyrolysis, allowing the expression of more abundant and perhaps more diverse Martian organic matter.

  17. Effects of the anti-thyroidal compound potassium-perchlorate on the thyroid system of the zebrafish

    Energy Technology Data Exchange (ETDEWEB)

    Schmidt, Florian, E-mail: florian.schmidt@zoo.uni-heidelberg.de [Aquatic Ecology and Toxicology Group, Centre for Organismal Studies, University of Heidelberg, Im Neuenheimer Feld 230, D-69120 Heidelberg (Germany); Schnurr, Sarah; Wolf, Raoul; Braunbeck, Thomas [Aquatic Ecology and Toxicology Group, Centre for Organismal Studies, University of Heidelberg, Im Neuenheimer Feld 230, D-69120 Heidelberg (Germany)

    2012-03-15

    The increasing pollution of aquatic habitats with anthropogenic compounds has led to various test strategies to detect hazardous chemicals. However, information on effects of pollutants in the thyroid system in fish, which is essential for growth, development and parts of reproduction, is still scarce. Other vertebrate groups such as amphibians or mammals are well-studied; so the need for further knowledge especially in fish as a favored vertebrate model test organism is evident. Modified early life-stage tests were carried out with zebrafish exposed to the known thyroid inhibitor potassium perchlorate (0, 62.5, 125, 250, 500 and 5000 {mu}g/L) to identify adverse effects on the hypothalamic-pituitary-thyroid axis. Especially higher perchlorate concentrations led to conspicuous alterations in thyroidal tissue architecture and to effects in the pituitary. In the thyroid, severe hyperplasia at concentrations {>=}500 {mu}g/L together with an increase in follicle number could be detected. The most sensitive endpoint was the colloid, which showed alterations at {>=}250 {mu}g/L. The tinctorial properties and the texture of the colloid changed dramatically. Interestingly, effects on epithelial cell height were minor. The pituitary revealed significant proliferations of TSH-producing cells resulting in alterations in the ratio of adeno- to neurohypophysis. The liver as the main site of T4 deiodination showed severe glycogen depletion at concentrations {>=}250 {mu}g/L. In summary, the thyroid system in zebrafish showed effects by perchlorate from concentrations {>=}250 {mu}g/L, thus documenting a high sensitivity of the zebrafish thyroid gland for goitrogens. In the future, such distinct alterations could lead to a better understanding and identification of potential thyroid-disrupting chemicals.

  18. Systematic evaluation of nitrate and perchlorate bioreduction kinetics in groundwater using a hydrogen-based membrane biofilm reactor.

    Science.gov (United States)

    Ziv-El, Michal C; Rittmann, Bruce E

    2009-01-01

    To evaluate the simultaneous reduction kinetics of the oxidized compounds, we treated nitrate-contaminated groundwater (approximately 9.4 mg-N/L) containing low concentrations of perchlorate (approximately 12.5 microg/L) and saturated with dissolved oxygen (approximately 8 mg/L) in a hydrogen-based membrane biofilm reactor (MBfR). We systematically increased the hydrogen availability and simultaneously varied the surface loading of the oxidized compounds on the biofilm in order to provide a comprehensive, quantitative data set with which to evaluate the relationship between electron donor (H(2)) availability, surface loading of the electron acceptors (oxidized compounds), and simultaneous bioreduction of the electron acceptors. Increasing the H(2) pressure delivered more H(2) gas, and the total H(2) flux increased linearly from approximately 0.04 mg/cm(2)-d for 0.5 psig (0.034 atm) to 0.13 mg/cm(2)-d for 9.5 psig (0.65 atm). This increased rate of H(2) delivery allowed for continued reduction of the acceptors as their surface loading increased. The electron acceptors had a clear hydrogen-utilization order when the availability of hydrogen was limited: oxygen, nitrate, nitrite, and then perchlorate. Spiking the influent with perchlorate or nitrate allowed us to identify the maximum surface loadings that still achieved more than 99.5% reduction of both oxidized contaminants: 0.21 mg NO(3)-N/cm(2)-d and 3.4 microg ClO(4)/cm(2)-d. Both maximum values appear to be controlled by factors other than hydrogen availability.

  19. Solution-reaction Calorimetric Study of Coordination Compounds of Rare Earth Perchlorates with Alanine and Imidazole

    Institute of Scientific and Technical Information of China (English)

    ZHAO, Yan-Ru(赵艳茹); HOU, An-Xin(侯安新); DONG, Jia-Xin(董家新); ZHAO, Shun-Sheng(赵顺省); LIU, Yi(刘义); QU, Song-Sheng(屈松生)

    2004-01-01

    Two coordination compounds of rare earth perchlorates with alanine and imidazole, [RE(Ala)n(Im)(H2O)](ClO4)3(s) (RE=La, n=3; RE=Nd, n=2), have been prepared and characterized. The standard molar enthalpies of reaction for the following two reactions, LaCL·7H2O(s)+3Ala(s)+Im(s)+3NaClO4(s)=[La(Ala).(Im)(H2O)]-(ClO4)3(s)+3NaCl(s)+6H2O(I)(1)and NdCl3·6H2O(s)+2Ala(s)+2Ala(s)+Im(s)+3NaClO4(s)=[Nd(Ala)2(Im)(H2O)]-(ClO4)3(s)+3NaCl(s)+5H2O(l) (2), were determined by solution-reaction calorimetry, at T=298.15 K, as 36.168 ±0.642kJ·mol-1 and 48.590±0.934kJ·mol-1 respectively. From the results and other auxiliary quantities, the standard molar enthalpies of formation of [La(Ala)3(Im)(H2O)](ClO4)3(s) and [Nd(Ala)2(Im)(H2O)] (ClO4)3(s) were derived,△fH(-)m{[La(Ala).(Im)(H2O)](ClO4)3,s}=(-2984.8±1.0)kJ·mol-1 and △fH(-)m{[Nd(Ala).(Im)(H2O)]-(ClO4)3,s}=(-2387.8±0.8)kJ·mol-1, respectively.

  20. Mössbauer study on the gamma radiolysis of anhydrous cesium tris (oxalato) ferrate(III)

    Science.gov (United States)

    Ladriere, J.; Senterre, V.; Apers, D.

    1992-04-01

    The final product of the gamma radiolysis of anhydrous cesium tris(oxalato) ferrate(III) has been identified by Mössbauer spectroscopy as Cs2Fe(ox)2. The radiolytic decomposition proceeds as a first-order process due to the original compound depletion and to the radiolytic stability of the ferrous compound. Lamb-Mössbauer factors measurements indicate that the recoilless fractions of the iron species are practically unaffected by the radiolysis.

  1. Spatial variability and the fate of cesium in coastal sediments near Fukushima, Japan

    Directory of Open Access Journals (Sweden)

    E. Black

    2014-05-01

    Full Text Available Quantifying the amount of cesium incorporated into marine sediments as a result of the Fukushima Dai-ichi Nuclear Power Plant (FDNPP accident has proven challenging due to the limited multi-core sampling from within the 30 km zone around the facility, the inherent spatial heterogeneities in ocean sediments, and the potential for inventory fluctuations due to physical, biological, and chemical processes. Using 210Pb, 234Th, 137Cs, and 134Cs profiles from 20 sediment cores, coastal sediment inventories were reevaluated. A minimum 137Cs sediment inventory of 100 ± 50 TBq was found for an area of 55 000 km2 using cores from this study and a total of 130 ± 60 TBq using an additional 181 samples. These inventories represent less than 1% of the estimated 15–30 PBq of cesium released during the FDNPP disaster and constitute ~ 90% of the total coastal inventory of 137Cs remaining in 2012. The time needed for surface sediment activities (0 to 3 cm at the 20 locations to reduce by 50% via bioturbation was estimated to range from 0.4 to 26 years, indicating a much greater persistence of cesium in the sediments relative to coastal water activities. However, due to the observed variability in mixing rates, grain size, and inventories, additional cores are needed to further improve estimates and capture the full extent of cesium penetration into the shallow coastal sediments, which was deeper than 14 cm for all cores retrieved from water depths less than 150 m.

  2. Prussian blue caged in spongiform adsorbents using diatomite and carbon nanotubes for elimination of cesium

    OpenAIRE

    Hu, Baiyang; Fugetsu, Bunshi; Yu, Hongwen; Abe, Yoshiteru

    2012-01-01

    We developed a spongiform adsorbent that contains Prussian blue, which showed a high capacity for eliminating cesium. An in situ synthesizing approach was used to synthesize Prussian blue inside diatomite cavities. Highly dispersed carbon nanotubes (CNTs) were used to form CNT networks that coated the diatomite to seal in the Prussian blue particles. These ternary (CNT/diatomite/Prussian-blue) composites were mixed with polyurethane (PU) prepolymers to produce a quaternary (PU/CNT/diatomite/P...

  3. The effects of different factors at the cesium 137 accumulation by tree plants

    International Nuclear Information System (INIS)

    It was shown that cesium 137 accumulation by tree plants depended from numerous factors that had to be take into account by utilisation of forest production and conducting of forestry in the whole. It is necessary to elaborate a new classification of contaminated forests which could take into account not only radionuclide density of soils but existence of different tree species and their growth conditions

  4. Evaporative cooling of cesium atoms in the gravito-optical surface trap

    CERN Document Server

    Hammes, M; Grimm, R

    2000-01-01

    We report on cooling of an atomic cesium gas closely above an evanescent-wave. Our first evaporation experiments show a temperature reduction from 10muK down to 300nK along with a gain in phase-space density of almost two orders of magnitude. In a series of measurements of heating and spin depolarization an incoherent background of resonant photons in the evanescent-wave diode laser light was found to be the limiting factor at this stage.

  5. Quantized atomic motion in 1D cesium molasses with magnetic field

    International Nuclear Information System (INIS)

    We report the observation of quantized energy levels for the motion of cesium atoms in optical molasses consisting two counterpropagating σ+ beams and a small transverse magnetic field. The observation of overtones proves the existence of at least four bound states in each optical potential well. The absorption spectrum is dramatically modified when an additional longitudinal magnetic field is applied. In particular, a population inversion between quantized levels is observed. (orig.)

  6. Strategic Design and Optimization of Inorganic Sorbents For Cesium, Strontium and Actinides

    Energy Technology Data Exchange (ETDEWEB)

    Hobbs, D.; Nyman, M.; Clearfield, A.; Maginn, E.

    2006-06-01

    The basic science goal in this project identifies structure/affinity relationships for selected radionuclides and existing sorbents. The task will apply this knowledge to the design and synthesis of new sorbents that will exhibit increased affinity for cesium, strontium and actinide separations. The target problem focuses on the treatment of high-level nuclear wastes. The general approach can likewise be applied to nonradioactive separations.

  7. Development of an Advanced Polymeric Composite (ALIX) for separation of cesium from nuclear waste

    International Nuclear Information System (INIS)

    137Cs is one of the major isotopes present in high level radioactive waste (HLW). Its presence makes nuclear waste handling difficult. A new composite (ALIX) containing Ammonium molybdophosphate and a derivative of Bisphenol was developed for column operations to selectively remove cesium from acidic high level nuclear waste. The composite is stable in nitric acid, radiation field and exhibits fast kinetics for uptake. The properties of the composite are attributed to molecular structure of the polymer and morphology of the composite. (author)

  8. Prussian blue as an antidote for radioactive thallium and cesium poisoning

    Directory of Open Access Journals (Sweden)

    Altagracia-Martinez M

    2012-06-01

    Full Text Available Marina Altagracia-Martínez, Jaime Kravzov-Jinich, Juan Manuel Martínez-Núñez, Camilo Ríos-Castañeda, Francisco López-NaranjoDepartments of Biological Systems and Health Care, Biological and Health Sciences Division, Universidad Autónoma Metropolitana-Xochimilco, Mexico DF, MexicoBackground: Following the attacks on the US on September 11, 2001, potentially millions of people might experience contamination from radioactive metals. However, before the specter of such accidents arose, Prussian blue was known only as an investigational agent for accidental thallium and cesium poisoning. The purpose of this review is to update the state of the art concerning use of Prussian blue as an effective and safe drug against possible bioterrorism attacks and to disseminate medical information in order to contribute to the production of Prussian blue as a biodefense drug.Methods: We compiled articles from a systematic review conducted from January 1, 1960 to March 30, 2011. The electronic databases consulted were Medline, PubMed, the Cochrane Library, and Scopus.Results: Prussian blue is effective and safe for use against radioactive intoxications involving cesium-137 and thallium. The US Food and Drug Administration has approved Prussian blue as a drug, but there is only one manufacturer providing Prussian blue to the US. Based on the evidence, Prussian blue is effective for use against radioactive intoxications involving cesium-137 and thallium, but additional clinical research on and production of Prussian blue are needed.Keywords: Prussian blue, radioactive cesium, thallium, intoxication, biodefense drug

  9. Laser-pumped cesium magnetometers for high-resolution medical and fundamental research

    OpenAIRE

    Groeger, Stephan; Bison, Georg; Knowles, Paul E.; Wynands, Robert; Weis, Antoine

    2007-01-01

    Laser-pumped cesium magnetometers allow highly sensitive magnetometry at room temperature. We report on applications of that technique in biomagnetic diagnostics and in a neutron electric dipole moment (nEDM) experiment. In the biomagnetic application the magnetic field from the beating human heart is detected using a gradiometer, which reaches an intrinsic sensitivity of 80 fT/Hz1/2. The device can record time-resolved magnetic field maps above the human body surface with a spatial resolutio...

  10. Cesium under pressure: First-principles calculation of the bcc-to-fcc phase transition

    Science.gov (United States)

    Carlesi, S.; Franchini, A.; Bortolani, V.; Martinelli, S.

    1999-05-01

    In this paper we present the ab initio calculation of the structural properties of cesium under pressure. The calculation of the total energy is done in the local-density approximation of density-functional theory, using a nonlocal pseudopotential including the nonlinear core corrections proposed by Louie et al. The calculation of the pressure-volume diagram for both bcc and fcc structures allows us to prove that the transition from bcc to fcc structure is a first-order transition.

  11. cis-Aquabis(2,2′-bipyridine-κ2N,N′fluoridochromium(III bis(perchlorate dihydrate

    Directory of Open Access Journals (Sweden)

    Torben Birk

    2010-02-01

    Full Text Available The title mixed aqua–fluoride complex, [CrF(C10H8N22(H2O](ClO42·2H2O, has been synthesized by aquation of the corresponding difluoride complex using lanthanide(III ions as F− acceptors. The complex crystallizes with a CrIII ion at the center of a distorted octahedral coordination polyhedron with a cis arrangement of ligands. The crystal packing shows a hydrogen-bonding pattern involving water molecules, the coordinated F atom and the perchlorate anions

  12. Preignition reactions of AP-HTPB propellants studied by IR spectrometry. [Ammonium Perchlorate-Hydroxyl Terminated PolyButadiene

    Science.gov (United States)

    Law, R. J.; Baer, A. D.; Ryan, N. W.

    1977-01-01

    IR absorption spectrometry was used to follow the disappearance of NH and CH bonds during the pyrolysis of a polymer film containing 30 weight percent ammonium perchlorate (AP). The remaining 70 weight percent consisted of a mixture of 92.5 weight percent hydroxyl-terminated polybutadiene (HTPB) and 7.5 weight percent isophrone diisocyanate (IPDI). The results indicate that polymer decomposition is induced by products of AP decomposition, and that about 2.5 CH bonds disappear for each NH bond that disappears. The diffusion process occurring in the later stages of the reaction is analyzed in an attempt to account for the unexpectedly low activation energy.

  13. On the adhesion between hydroxyl-terminated polybutadiene fuel-binder and ammonium perchlorate. Performance of bonding agents

    Energy Technology Data Exchange (ETDEWEB)

    Hori, K.; Iwama, A.; Fukuda, T.

    1985-12-01

    A simple method to evaluate the adhesive force between solid oxidizer and polymeric fuel-binder is presented. As an illustration, hydroxyl-terminated polybutadiene (HTPB) sticks including several different bonding agents are bonded on ammonium perchlorate (AP) single crystals, and stress-strain history unitl rupture occurs is obtained by applying uniaxial tensile stress perpendicularly to the adhesion surface. Further, whether each bonding agent reacts with AP or not was analysed with pursuing infrared absorption spectra. The hypothesis that the interfacial adhesive force arises from hydrogen bonding force is proposed.

  14. Kinetics and mechanism of oxidation of glycine by iron(III)-1,10-phenanthroline complex in perchloric acid medium

    Indian Academy of Sciences (India)

    T V N Partha Sarathi; A Kalyan Kumar; K Krishna Kishore; P Vani

    2005-07-01

    Kinetics and mechanism of oxidation of glycine by iron(III)-1,10-phenanthroline complex has been studied in perchloric acid medium. The reaction is first order with respect to iron(III) and glycine. An increase in (phenanthroline) increases the rate, while increase in [H+] decreases the rate. Hence it can be inferred that the reactive species of the substrate is the zwitterionic form and that of the oxidant is [Fe(phen)2(H2O)2]3+. The proposed mechanism leads to the rate law as elucidated.

  15. Photoemission from Graphene on Copper and Cesium Antimonide: Theory and Experiment

    Science.gov (United States)

    Finkenstadt, Daniel; Jensen, Kevin L.; Lambrakos, Samuel G.; Shabaev, Andrew; Moody, Nathan A.

    The work function is calculated using DFT for a substrate of flat copper on which a single layer of graphene is deposited. These calculations show a reduced work function, compared to bare copper, when graphene is deposited on a cathode. Based on our DFT-calculated results, a simple model using the transfer matrix approach gives the transmission probability near and above the barrier maximum. An important element of our model is the DFT-calculated, macroscopically-averaged electrostatic potential. Using this potential, graphene behaves as a resonant well for electrons transmitted between the substrate and vacuum regions. Another system to be discussed is graphene atop cesium antimonide, which has very low work function making it technologically useful, in particular for the development of an x-ray free electron laser. On cesium antimonide, we examine whether graphene may allow for the retention of an underlying cesium layer that is often damaged in high-field applications. A discussion of these results in light of recent experimental characterization at LANL will be given. Funding and support provide by ONR and DOE.

  16. Uptake and transport of radioactive cesium and strontium into grapevines after leaf contamination

    Science.gov (United States)

    Zehnder, H. J.; Kopp, P.; Eikenberg, J.; Feller, U.; Oertli, J. J.

    1995-07-01

    From 1989 to 1993 the foliar uptake of radioactive strontium (Sr-85) and cesium (Cs-134) by selected leaves of grapevine plants and the subsequent redistribution within the plants was examined under controlled conditions in a greenhouse. The radionuclides were applied as chlorides. These plants were grown in large pots containing a mixture of local soil and peat. Plant and soil samples were analyzed throughout the growing season and also during the following vegetation period. Only traces of the applied radiostrontium were taken up by the leaves. This element was essentially not redistributed within the plants. In contrast, radiocesium was easily taken up through the leaf surface, transported to other plant parts and to some extent released from the roots into the soil. Cesium reaching the soil may interact with clay particles causing a very reduced availability for plants. Therefore the soil may act as a long-term sink for radiocesium. On the other hand, grape berries represent transient sinks. The cesium levels in the berries decreased again in a late phase of maturation, but the mechanisms causing this loss are not yet identified. During the second vegetation period, only a very minor proportion of the radiocesium taken up previously by the plants was present in the above ground parts.

  17. Strontium-90 and cesium-137 in soil from May to July 1983

    International Nuclear Information System (INIS)

    The measured values in soil of strontium-90 and cesium-137 at a total of 4 locations throughout Japan from May to July, 1983 are given in pCi/kg and mCi/km2 in the tables. The method of measurement is also described: collection and pretreatment of samples, preparation of the samples for analysis, separation of strontium-90 and cesium-137, determination of stable strontium, calcium and potassium, and counting. Soil was collected from the location in the spacious and flat area without any past disturbance. Soil was taken from two layers having different depths: 0--5 cm and 5--20 cm. The sample solution was neutralized with sodium hydroxide. After sodium carbonate was added, the precipitate of strontium and calcium carbonates was separated. The supernatant solution was retained for cesium-137 determination. After the radiochemical separation, the mounted precipitates were counted for activity using a low background beta counter normally for 60 min. The maximum values were 690 pCi/kg for Sr-90 and 1300 pCi/kg for Cs-137, which were obtained from the samples in the 5-to-20 cm depth, in June 1983, at Akita-ken,Japan. (Mori, K.)

  18. Enhanced capacity and stability for the separation of cesium in electrically switched ion exchange

    Energy Technology Data Exchange (ETDEWEB)

    Tawfic, A.F.; Dickson, S.E.; Kim, Y. [McMaster University, Hamilton, ON (Canada); Mekky, W. [AMEC NSS, Power and Process America, Toronto (Canada)

    2015-03-15

    Electrically switched ion exchange (ESIX) can be used to separate ionic contaminants from industrial wastewater, including that generated by the nuclear industry. The ESIX method involves sequential application of reduction and oxidation potentials to an ion exchange film to induce the respective loading and unloading of cesium. This technology is superior to conventional methods (e.g electrodialysis reversal or reverse osmosis) as it requires very little energy for ionic separation. In previous studies, ESIX films have demonstrated relatively low ion exchange capacities and limited film stabilities over repeated potential applications. In this study, the methodology for the deposition of electro-active films (nickel hexacyanoferrate) on nickel electrodes was modified to improve the ion exchange capacity for cesium removal using ESIX. Cyclic voltammetry was used to investigate the ion exchange capacity and stability. Scanning electron microscopy (SEM) was used to characterize the modified film surfaces. Additionally, the films were examined for the separation of cesium ions. This modified film preparation technique enhanced the ion exchange capacity and improves the film stability compared to previous methods for the deposition of ESIX films. (authors)

  19. Kinetic and equilibrium studies of cesium adsorption on ceiling tiles from aqueous solutions

    Energy Technology Data Exchange (ETDEWEB)

    Miah, Muhammed Yusuf [Emergencies Science and Technology Section, Environment Canada, 335 River Road, Ottawa, Ontario, K1A 0H3 (Canada); Department of Applied Chemistry and Chemical Technology, Noakhali Science and Technology University (Bangladesh); Volchek, Konstantin, E-mail: Konstantin.Volchek@ec.gc.ca [Emergencies Science and Technology Section, Environment Canada, 335 River Road, Ottawa, Ontario, K1A 0H3 (Canada); Kuang, Wenxing [SAIC Canada, 335 River Road, Ottawa, Ontario, K1A 0H3 (Canada); Tezel, F. Handan [Department of Chemical and Biological Engineering, University of Ottawa, 161 Louis-Pasteur, Ottawa, Ontario, K1N 6N5 (Canada)

    2010-11-15

    A series of experiments were performed to quantify the adsorption of cesium on ceiling tiles as a representative of urban construction materials. Adsorption was carried out from solutions to mimic wet environmental conditions. Non-radioactive cesium chloride was used as a surrogate of the radioactive {sup 137}Cs. The experiments were performed in the range of initial cesium concentrations of 0.114-23.9 mg L{sup -1} at room temperature (21 deg. C) around three weeks. Solution samples were taken after set periods of time and analyzed by inductively coupled plasma mass spectrometry (ICP-MS). The quantity of adsorbed Cs was calculated by mass balance as a function of time. Two kinetic and three equilibrium models were employed to interpret the test results. Determination of kinetic parameters for adsorption was carried out using the first-order reaction model and the intra-particle diffusion model. Adsorption equilibrium was studied using Langmuir, Freundlich and three-parameter Langmuir-Freundlich adsorption isotherm models. A satisfactory correlation between the experimental and the predicted values was observed.

  20. Derivation of cesium-137 residual radioactive material guidelines for the Peek Street site, Schenectady, New York

    Energy Technology Data Exchange (ETDEWEB)

    Jones, L.; Nimmagadda, M.; Yu, C.

    1992-01-01

    Residual radioactive material guidelines for cesium-137 were derived for the Peek rk. The derivation was based on the requirement that the Street site in Schenectady, New York. The derivation was based on the requirement that the 50-year committed effective dose equivalent to a hypothetical individual who lives or works in the immediate vicinity of the Peek Street site should not exceed a dose of 100 mrem/yr following remedial action. The US Department of Energy (DOE) residual radioactive material guideline computer code, RESRAD was used in this evaluation. Three potential scenarios were considered for the site on the assumption that for a period of 1,000 years following remedial action, the site wig be utilized without radiological restrictions. The scenarios vary with regard to use of the site, time spent at the site, and sources of food consumed. Results indicate that the basic dose limit of 100 mrem/yr will not be exceeded for cesium-137 within 1,000 years, provided that the soil concentration of cesium-137 at the Peek Street site does not exceed the following levels: 98 pCi/g for Scenario A (industrial worker: the expected scenario), 240 pCi/g for Scenario B (recreationist: a plausible scenario), and 34 pCi/g for Scenario C (resident farmer ingesting food produced in the decontaminated area: a plausible scenario).

  1. Cesium and strontium tolerant Arthrobacter sp. strain KMSZP6 isolated from a pristine uranium ore deposit.

    Science.gov (United States)

    Swer, Pynskhem Bok; Joshi, Santa Ram; Acharya, Celin

    2016-12-01

    Arthrobacter sp. KMSZP6 isolated from a pristine uranium ore deposit at Domiasiat located in North-East India exhibited noteworthy tolerance for cesium (Cs) and strontium (Sr). The strain displayed a high minimum inhibitory concentration (MIC) of 400 mM for CsCl and for SrCl2. Flow cytometric analysis employing membrane integrity indicators like propidium iodide (PI) and thiazole orange (TO) indicated a greater sensitivity of Arthrobacter cells to cesium than to strontium. On being challenged with 75 mM of Cs, the cells sequestered 9612 mg Cs g(-1) dry weight of cells in 12 h. On being challenged with 75 mM of Sr, the cells sequestered 9989 mg Sr g(-1) dry weight of cells in 18 h. Heat killed cells exhibited limited Cs and Sr binding as compared to live cells highlighting the importance of cell viability for optimal binding. The association of the metals with Arthrobacter sp. KMSZP6 was further substantiated by Field Emission-Scanning Electron Microscopy (FE-SEM) coupled with Energy dispersive X-ray (EDX) spectroscopy. This organism tolerated up to 1 kGy (60)Co-gamma rays without loss of survival. The present report highlights the superior tolerance and binding capacity of the KMSZP6 strain for cesium and strontium over other earlier reported strains and reveals its potential for bioremediation of nuclear waste. PMID:27620733

  2. Study on magnetic separation for decontamination of cesium contaminated soil by using superconducting magnet

    International Nuclear Information System (INIS)

    Highlights: • The method for the soil decontamination by the superconducting magnet is proposed. • Magnetic separation of clay minerals was performed by HGMS. • Soil separation ratio was evaluated by quantitative analysis using XRD. • It is expected that HGMS can be applied to the actual soil decontamination. - Abstract: The accident of Fukushima Daiichi nuclear power plant caused the diffusion of radioactive cesium over the wide area. We examined the possibility of applying magnetic separation method using the superconducting magnet, which can process a large amount of the soil in high speed, to the soil decontamination and volume reduction of the radioactive cesium contaminated soil. Clay minerals are classified as 2:1 and 1:1 types by the difference of their layer structures, and these types of minerals are respectively paramagnetic and diamagnetic including some exception. It is known that most of the radioactive cesium is strongly adsorbed on the clay, especially on 2:1 type clay minerals. It is expected that the method which can separate only 2:1 type clay minerals selectively from the mixture clay minerals can enormously contribute to the volume reduction of the contaminated soil. In this study, the components in the clay before and after separation were evaluated to estimate the magnetic separation efficiency by using X-ray diffraction. From the results, the decontamination efficiency and the volume reduction ratio were estimated in order to examine the appropriate separation conditions for the practical decontamination of the soil

  3. ION EXCHANGE MODELING FOR REMOVAL OF CESIUM FROM HANFORD WASTE USING SUPERLIG 644 RESIN

    Energy Technology Data Exchange (ETDEWEB)

    Hamm, L

    2004-05-01

    The expected performance of a proposed ion exchange column using SuperLig{reg_sign} 644 resin for the removal of cesium from Hanford high level radioactive alkaline waste is discussed. This report represents a final report on the ability and knowledge with regard to modeling the Cesium-SuperLig{reg_sign} 644 resin ion exchange system. Only the loading phase of the cycle process is addressed within this report. Pertinent bench-scale column tests and batch equilibrium experiments are addressed. The methodology employed and sensitivity analyses are also included (i.e., existing methodology employed is referenced to prior developmental efforts while updated methodology is discussed). Pilot-scale testing is not assessed since no pilot-scale testing was available at the time of this report. Column performance predictions are made considering three selected feed compositions under nominal operating conditions. The sensitivity analyses provided help to identify key parameters that aid in resin procurement acceptance criteria. The methodology and application presented within this report reflect the expected behavior of SuperLig{reg_sign} 644 resin manufactured at the production-scale (i.e, 250 gallon batch size level). The primary objective of this work was, through modeling and verification based on experimental assessments, to predict the cesium removal performance of SuperLig{reg_sign} 644 resin for application in the RPP pretreatment facility.

  4. Derivation of cesium-137 residual radioactive material guidelines for the Peek Street site, Schenectady, New York

    International Nuclear Information System (INIS)

    Residual radioactive material guidelines for cesium-137 were derived for the Peek rk. The derivation was based on the requirement that the Street site in Schenectady, New York. The derivation was based on the requirement that the 50-year committed effective dose equivalent to a hypothetical individual who lives or works in the immediate vicinity of the Peek Street site should not exceed a dose of 100 mrem/yr following remedial action. The US Department of Energy (DOE) residual radioactive material guideline computer code, RESRAD was used in this evaluation. Three potential scenarios were considered for the site on the assumption that for a period of 1,000 years following remedial action, the site wig be utilized without radiological restrictions. The scenarios vary with regard to use of the site, time spent at the site, and sources of food consumed. Results indicate that the basic dose limit of 100 mrem/yr will not be exceeded for cesium-137 within 1,000 years, provided that the soil concentration of cesium-137 at the Peek Street site does not exceed the following levels: 98 pCi/g for Scenario A (industrial worker: the expected scenario), 240 pCi/g for Scenario B (recreationist: a plausible scenario), and 34 pCi/g for Scenario C (resident farmer ingesting food produced in the decontaminated area: a plausible scenario)

  5. Study on magnetic separation for decontamination of cesium contaminated soil by using superconducting magnet

    Energy Technology Data Exchange (ETDEWEB)

    Igarashi, Susumu, E-mail: igarashi@qb.see.eng.osaka-u.ac.jp; Nomura, Naoki; Mishima, Fumihito; Akiyama, Yoko, E-mail: yoko-ak@see.eng.osaka-u.ac.jp

    2014-09-15

    Highlights: • The method for the soil decontamination by the superconducting magnet is proposed. • Magnetic separation of clay minerals was performed by HGMS. • Soil separation ratio was evaluated by quantitative analysis using XRD. • It is expected that HGMS can be applied to the actual soil decontamination. - Abstract: The accident of Fukushima Daiichi nuclear power plant caused the diffusion of radioactive cesium over the wide area. We examined the possibility of applying magnetic separation method using the superconducting magnet, which can process a large amount of the soil in high speed, to the soil decontamination and volume reduction of the radioactive cesium contaminated soil. Clay minerals are classified as 2:1 and 1:1 types by the difference of their layer structures, and these types of minerals are respectively paramagnetic and diamagnetic including some exception. It is known that most of the radioactive cesium is strongly adsorbed on the clay, especially on 2:1 type clay minerals. It is expected that the method which can separate only 2:1 type clay minerals selectively from the mixture clay minerals can enormously contribute to the volume reduction of the contaminated soil. In this study, the components in the clay before and after separation were evaluated to estimate the magnetic separation efficiency by using X-ray diffraction. From the results, the decontamination efficiency and the volume reduction ratio were estimated in order to examine the appropriate separation conditions for the practical decontamination of the soil.

  6. DFB-ridge laser diodes at 894 nm for Cesium atomic clocks

    Science.gov (United States)

    von Bandel, N.; Garcia, M.; Lecomte, M.; Larrue, A.; Robert, Y.; Vinet, E.; Driss, O.; Parrilaud, O.; Krakowski, M.; Gruet, F.; Matthey, R.; Mileti, G.

    2016-02-01

    Time and frequency applications are in need of high accuracy and high stability clocks. Optically pumped compact industrial Cesium atomic clocks are a promising approach that could satisfy these demands. However, the stability of these clocks relies, among others, on the performances of the laser diodes that are used. This issue has led the III-V Lab to commit to the European Euripides-LAMA project that aims to provide competitive compact optical Cesium clocks for ground applications. This work will provide key experience for further space technology qualification. III-V Lab is in charge of the design, fabrication and reliability of Distributed-Feedback diodes (DFB) at 894 nm (D1 line of Cesium) and 852 nm (D2 line). LTF-Unine is in charge of their spectral characterisation. The use of D1 line for pumping will provide simplified clock architecture compared to the D2 line pumping thanks to simpler atomic transitions and a larger spectral separation between lines in the 894 nm case. Also, D1 line pumping overcomes the issue of unpumped "idle states" that occur with D2 line. The modules should provide narrow linewidth (= 10 Hz and 109 Hz2/Hz @ f >= 10 Hz.

  7. ION EXCHANGE MODELING FOR REMOVAL OF CESIUM FROM HANFORD WASTE USING SUPERLIG 644 RESIN

    International Nuclear Information System (INIS)

    The expected performance of a proposed ion exchange column using SuperLig(regsign) 644 resin for the removal of cesium from Hanford high level radioactive alkaline waste is discussed. This report represents a final report on the ability and knowledge with regard to modeling the Cesium-SuperLig(regsign) 644 resin ion exchange system. Only the loading phase of the cycle process is addressed within this report. Pertinent bench-scale column tests and batch equilibrium experiments are addressed. The methodology employed and sensitivity analyses are also included (i.e., existing methodology employed is referenced to prior developmental efforts while updated methodology is discussed). Pilot-scale testing is not assessed since no pilot-scale testing was available at the time of this report. Column performance predictions are made considering three selected feed compositions under nominal operating conditions. The sensitivity analyses provided help to identify key parameters that aid in resin procurement acceptance criteria. The methodology and application presented within this report reflect the expected behavior of SuperLig(regsign) 644 resin manufactured at the production-scale (i.e, 250 gallon batch size level). The primary objective of this work was, through modeling and verification based on experimental assessments, to predict the cesium removal performance of SuperLig(regsign) 644 resin for application in the RPP pretreatment facility

  8. Stationary point of the radiometric control of cesium contamination of agricultural animals

    International Nuclear Information System (INIS)

    Stationary point of the radiometric control of cesium contamination of an agricultural animals. Is intended for vital measurements of the contents of radiocesium in muscular tissue of a cattle. Can be used on cattle-breeding farms, providing points, in meat factories and personal facilities. As a base means for accommodation of the control point the motor-car is used. Design of the car allows to automate operations on deployment of the control point on a place and translation of one to a transport mode. Limits of measured specific activity of cesium contamination of a cattle is up 5*10-9 to 5*10-6 Ci/kg. The basic error on the bottom limit of measurement at confidence coefficient 0,95 is no more than 30%. Measurement time for the bottom limit of determined specific activity is no more than 30 s. There is automatic measurement mode. Type of a power is 220 V, 50 Hz. Range of working temperatures is up -15 to +35 centigrade. Relative humidity is no more than 98% at 25 centigrade. External gamma background is till 0.035 mR/h. Time of installation and dismantle of stationary control point is no more than 1,5 hours. The direct radiometric control in divo allows to fulfil and to use biotechnological process of removing of cesium isotopes from body of animals for decrease of levels of radioactive contamination

  9. Crown bridged thiacalix[4]arenes as cesium-selective ionophores in solvent polymeric membrane electrodes

    Energy Technology Data Exchange (ETDEWEB)

    Bereczki, Robert [Technical Analytical Research Group of the Hungarian Academy of Sciences, Department of General and Analytical Chemistry, Budapest University of Technology and Economics, Szt. Gellert ter 4, H-1111 Budapest (Hungary); Csokai, Viktor [Department of Organic Chemical Technology, Budapest University of Technology and Economics, Muegyetem rkp.3, H-1111 Budapest (Hungary); Gruen, Alajos [Department of Organic Chemical Technology, Budapest University of Technology and Economics, Muegyetem rkp.3, H-1111 Budapest (Hungary); Bitter, Istvan [Department of Organic Chemical Technology, Budapest University of Technology and Economics, Muegyetem rkp.3, H-1111 Budapest (Hungary); Toth, Klara [Technical Analytical Research Group of the Hungarian Academy of Sciences, Department of General and Analytical Chemistry, Budapest University of Technology and Economics, Szt. Gellert ter 4, H-1111 Budapest (Hungary)]. E-mail: ktoth@mail.bme.hu

    2006-05-31

    Novel 1,3-alternate thiacalix[4]mono- and biscrown-6 ethers were studied as ionophores in poly(vinyl chloride) membrane electrodes. Their selectivity behavior was characterized with respect to large number of cations, including potential interferents in environmental samples, and the membrane composition was optimized for cesium ion response. Among the ionophores, 1,3-alternate thiacalix[4]mono(crown-6) ether showed, especially high selectivity for cesium over other alkali-metal ions. Transition and heavy metal ions did not interfere seriously with the electrode response, which indicates that the bridging sulfur atoms do not take part in the ion recognition process. The potentiometric cesium responses of all electrodes involved in this study were found close to Nernstian and the detection limits were lower than 10{sup -7} M. The Cs{sup +}/Na{sup +} selectivity of the different ionophore-based sensors and the solvent extraction ability of the ligands were interpreted based on the respective constants of complex formation.

  10. Temperature and number evolution of cold cesium atoms inside a wall-coated glass cell

    Institute of Scientific and Technical Information of China (English)

    黄家强; 张建伟; 王时光; 王力军

    2015-01-01

    We report an experimental study on the temperature and number evolution of cold cesium atoms diffusively cooled inside a wall-coated glass cell by measuring the absorption profile of the 62S1/2 (F=4)→62P3/2(F0=5) transition line with a weak probe laser in the evolution process. We found that the temperature of the cold atoms first gradually decreases from 16 mK to 9 mK, and then rapidly increases. The number of cold atoms first declines slowly from 2.1 × 109 to 3.7 × 108 and then falls drastically. A theoretical model for the number evolution is built and includes the instantaneous temperature of the cold atoms and a fraction p, which represents the part of cold cesium atoms elastically reflected by the coated cell wall. The theory is overall in good agreement with the experimental result, and a nonzero value is obtained for the fraction p, which indicates that the cold cesium atoms are not all heated to the ambient temperature by a single collision with the coated cell wall. These results can provide helpful insight for precision measurements based on diffuse laser cooling.

  11. Small-Scale Ion Exchange Removal of Cesium and Technetium from Hanford Tank 241-AN-103

    Energy Technology Data Exchange (ETDEWEB)

    Hassan, N.M.

    2000-07-27

    The pretreatment process for BNFL, Inc.'s Hanford River Protection Project is to provide decontaminated low activity waste and concentrated eluate streams for vitrification into low activity and high level waste glass, respectively. The pretreatment includes sludge washing, filtration, precipitation, and ion exchange processes to remove entrained solids, cesium, transuranics, technetium, and strontium. The ion exchange removal of cesium (Cs) and technetium (Tc) ions is accomplished by using SuperLig 644, and 639 resins from IBC Advanced Technologies, American Fork, Utah. The resins were shown to selectively remove cesium and technetium (as pertechnetate), from alkaline salt solutions. The efficiency of ion exchange column loading and elution is a complex function involving feed compositions, equilibrium and kinetic behavior of ion exchange resins, diffusion, and the ionic strength and pH of the aqueous solution. A previous experimental program completed at the Savannah River Technology Center demonstrated the conceptualized flow sheet parameters with a similar Hanford tank sample (241-AW-101). Those experiments included determination of Cs and Tc batch distribution coefficients by SuperLig 644 and 639 resins and demonstration of small-scale column breakthrough and elution. The experimental findings were used in support of preliminary design bases and pretreatment flow sheet development by BNFL, Inc.

  12. Determination of collisional ionization rate and ionization yield from excited levels of cesium in a flame

    International Nuclear Information System (INIS)

    A method is proposed for determining the rate constants of collisional ionization and the ionization yield from excited levels of cesium atoms in a flame, using experimental curves of optical saturation and laser-stimulated ionization of excited atoms. It is shown that deviations of the shape of the saturation curves from ideal shape are due to the time dependence of the trailing edge of the exciting laser pulse. The ionization yield of cesium in an acetylene--air flame during its one-step excitation to the 6p2p1/2 level was 0.95%, rising to 50% for two-step excitation to the 8d2D3/2 level. The corresponding values of the rate constants of collisional ionization were 3.2x105 and 3.3x107 sec-1. From the known value of the ionization yield in the two-step excitation scheme, estimates of the atomization coefficient of cesium in the flame were made. The proposed method can be used for other elements in different flames

  13. Temperature and number evolution of cold cesium atoms inside a glass cell

    CERN Document Server

    Huang, J Q; Wang, S G; Wang, Z B; Wang, L J

    2015-01-01

    We report an experimental study on the temperature and number evolution of the cold cesium atoms diffusively cooled inside a wall-coated glass cell by measuring the absorption profile of the 62S1/2 (F=4)-62P3/2 (F'=5) transition line with a weak probe laser in the evolution process. We found that the temperature of the cold atoms first gradually decreases from 16 mK to 9 mK, and then rapidly increases. A theoretical model of the number evolution is built, which includes the temperature of the cold atoms and the fraction p of the cold cesium atoms elastically reflected by the cell wall. The theoretical model is consistent with the experimental result very well, and the fraction p is obtained to be (0.58 +/- 0.03), which reveals that the cold cesium atoms are not all heated to the ambient temperature by a single collision with the cell wall.

  14. Fire Safety Tests for Cesium-Loaded Spherical Resorcinol Formaldehyde Resin: Data Summary Report

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Dong-Sang; Schweiger, Michael J.; Peterson, Reid A.

    2012-09-01

    A draft safety evaluation of the scenario for spherical resorcinol formaldehyde (SRF) resin fire inside the ion exchange column was performed by the Hanford Tank Waste Treatment and Immobilization Plant (WTP) Fire Safety organization. The result of this draft evaluation suggested a potential change of the fire safety classification for the Cesium Ion Exchange Process System (CXP) emergency elution vessels, equipment, and piping. To resolve this question, the fire properties of the SRF resin were measured by Southwest Research Institute (SwRI) through a subcontract managed by Pacific Northwest National Laboratory (PNNL). The results of initial fire safety tests on the SRF resin were documented in a previous report (WTP-RPT-218). The present report summarizes the results of additional tests performed by SwRI on the cesium-loaded SRF resin. The efforts by PNNL were limited to summarizing the test results provided by SwRI into one consolidated data report. The as-received SwRI report is attached to this report in the Appendix A. Where applicable, the precision and bias of each test method, as given by each American Society for Testing and Materials (ASTM) standard procedure, are included and compared with the SwRI test results of the cesium-loaded SRF resin.

  15. Optically pumped semiconductor lasers: Conception and characterization of a single mode source for Cesium atoms manipulation

    International Nuclear Information System (INIS)

    Lasers currently used in atomic clocks or inertial sensors are suffering from a lack of power, narrow linewidth or compactness for future spatial missions. Optically pumped semiconductor lasers, which combine the approach of classical solid state lasers and the engineering of semiconductor laser, are considered here as a candidate to a metrological laser source dedicated to the manipulation of Cesium atoms in these instruments. These lasers have demonstrated high power laser emission in a circular single transverse mode, as well as single longitudinal mode emission, favoured by the semiconductor structure and the external cavity design. We study the definition and the characterization of a proper semiconductor structure for the cooling and the detection of Cesium atoms at 852 nm. A compact and robust prototype tunable on the Cesium D2 hyperfine structure is built. The laser frequency is locked to an atomic transition thanks to a saturated absorption setup. The emission spectral properties are investigated, with a particular attention to the laser frequency noise and the laser linewidth. Finally, we describe and model the thermal properties of the semiconductor structure, which enables the simulation of the laser power characteristic. The experimental parameters are optimised to obtain the maximum output power with our structure. Thanks to our analysis, we propose several ways to overcome these limitations, by reducing the structure heating. (authors)

  16. Cesium removal demonstration utilizing crystalline silicotitanate sorbent for processing Melton Valley Storage Tank supernate: Final report

    Energy Technology Data Exchange (ETDEWEB)

    Walker, J.F. Jr.; Taylor, P.A.; Cummins, R.L. [and others

    1998-03-01

    This report provides details of the Cesium Removal Demonstration (CsRD), which was conducted at Oak Ridge National Laboratory (ORNL) on radioactive waste from the Melton Valley Storage Tanks. The CsRD was the first large-scale use of state-of-the-art sorbents being developed by private industry for the selective removal of cesium and other radionuclides from liquid wastes stored across the DOE complex. The crystalline silicotitanate sorbent used in the demonstration was chosen because of its effectiveness in laboratory tests using bench-scale columns. The demonstration showed that the cesium could be removed from the supernate and concentrated on a small-volume, solid waste form that would meet the waste acceptance criteria for the Nevada Test Site. During this project, the CsRD system processed > 115,000 L (30,000 gal) of radioactive supernate with minimal operational problems. Sluicing, drying, and remote transportation of the sorbent, which could not be done on a bench scale, were successfully demonstrated. The system was then decontaminated to the extent that it could be contact maintained with the use of localized shielding only. By utilizing a modular, transportable design and placement within existing facilities, the system can be transferred to different sites for reuse. The initial unit has now been removed from the process building and is presently being reinstalled for use in baseline operations at ORNL.

  17. Fabrication of stimuli-sensitive hydrogel for the removal of cesium

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Hee-Man; Bong, Sang Bum; Park, Chan Woo; Lee, Kune Woo; Seo, Bum-Kyoung; Moon, Jei Kwon [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2015-05-15

    The nuclear accident at the Fukushima Daiichi nuclear power station in 2011 released a huge quantity of radioactive contaminants into the environment.1 Among these, cesium Cs-137 is the most problematic contaminant due to its long half-life (30.2 years), and high-energy gamma ray (γ-ray) emissions. 2 Various surface including road, roof, house, building were contaminated with Cs-137. These coating materials have some problems and limitation such as toxic component, and lack of reusability of materials related to the cost. Thus, a more cost-effective and environmental friendly coating materials is still desired. 3 In the present study, the stimuli-sensitive hydrogel were fabricated for the removal of radioactive Cs from solid surface. We describe the morphology, structure, and physical property of these stimuli sensitive hydrogel. In addition, their ability to eliminate cesium was also evaluated. The smart hydrogel coating materials showed an excellent morphology change from the liquid to film by addition of Ca ion. Therefore, the stimuli-sensitive hydrogel demonstrated good potential for the treatment of contaminated surface for the removal of radioactive cesium.

  18. The effect of organic amendment on mobility of cesium in tropical soils - The effect of organic amendment on sorption mechanisms for cesium and cobalt in tropical soils

    Energy Technology Data Exchange (ETDEWEB)

    Wasserman, M.A.V.; Santos-Oliveira, R. [Instituto de Engenharia nuclear/CNEN. Rua Helio de Almeida, 75. Cidade Universitaria - Ilha do Fundao, Rio de Janeiro, RJ. CEP 21941-906 (Brazil); Garcia, R.J.L.; Ferreira, A.C.M.; Rochedo, E.R.R.; Sobrinho, G.A.N. [Instituto de Radioprotecao e Dosimetria/CNEN. Av. Salvador Allende s /no. Rio de Janeiro, RJ. CEP: 22780-160 (Brazil); Perez, D.V. [Centro Nacional de Pesquisa de Solos/EMBRAPA. R. Jardim Botanico, 1024.Rio de Janeiro, RJ, CEP: 22460-000 (Brazil); Wasserman, J.C. [dUFF Network of Environment and Sustainable Development (REMADS-UFF), University Federal Fluminense, Niteroi, RJ (Brazil)

    2014-07-01

    This work aimed to investigate the mechanisms involved in the sorption of {sup 137}Cs and {sup 60}Co as a function of the physico-chemical properties of some types of Brazilian soils and the changes on the behavior of these radionuclides due to changes in soil properties promoted by organic amendment. The experimental study was conducted in a controlled area, where pots containing different types of soils (Ferralsol, Nitisol and Histosol) and different doses of organic amendment (no amendment; 2 kg.m{sup -2} and 4 kg.m{sup -2}) were spiked with {sup 137}Cs and {sup 60}Co. The organic amendment used in this experiment was obtained in the Unit of Compost of the Organic Material of Pinheiral (RJ, Brazil), where the compost is made up from the leaves swept from the streets of the Pinheiral city. The mobility of these radionuclides in the soil was assessed through sequential chemical extraction and desorption studies as a function of pH. The bioavailability was evaluated through the effective absorption of radionuclide by root crops (Raphanus sativus, L). This study evidenced that the organic amendment plays an important role in the desorption processes of cobalt and cesium, reducing desorption of both nuclides beneath higher organic amendment dose. This behavior was observed in acid conditions as well in alkaline. However extreme acid conditions may mobilize both radionuclides, although cobalt mobility was shown to be more sensitive to low pH than cesium. (authors)

  19. The effect of organic amendment on mobility of cesium in tropical soils - The effect of organic amendment on sorption mechanisms for cesium and cobalt in tropical soils

    International Nuclear Information System (INIS)

    This work aimed to investigate the mechanisms involved in the sorption of 137Cs and 60Co as a function of the physico-chemical properties of some types of Brazilian soils and the changes on the behavior of these radionuclides due to changes in soil properties promoted by organic amendment. The experimental study was conducted in a controlled area, where pots containing different types of soils (Ferralsol, Nitisol and Histosol) and different doses of organic amendment (no amendment; 2 kg.m-2 and 4 kg.m-2) were spiked with 137Cs and 60Co. The organic amendment used in this experiment was obtained in the Unit of Compost of the Organic Material of Pinheiral (RJ, Brazil), where the compost is made up from the leaves swept from the streets of the Pinheiral city. The mobility of these radionuclides in the soil was assessed through sequential chemical extraction and desorption studies as a function of pH. The bioavailability was evaluated through the effective absorption of radionuclide by root crops (Raphanus sativus, L). This study evidenced that the organic amendment plays an important role in the desorption processes of cobalt and cesium, reducing desorption of both nuclides beneath higher organic amendment dose. This behavior was observed in acid conditions as well in alkaline. However extreme acid conditions may mobilize both radionuclides, although cobalt mobility was shown to be more sensitive to low pH than cesium. (authors)

  20. The Effect of Pressure and Organic Constituents on the Cesium Ion Exchange Performance of IONSIV IE-911

    International Nuclear Information System (INIS)

    This study examined cesium (137Cs) ion exchange of crystalline silicotitanate (CST) in simulated waste solution. In particular, the study focused on the effect of CST pretreatment on the kinetics and extent of cesium adsorption. The test used IONSIV IE-911 (UOP LLC, Molecular Sieves Division, Des Plaines, IL), the engineered form of CST. Pretreatment steps examined include: soaking CST in 2M NaOH solution for three days, exposing CST to 50% relative humidity for one week, flowing organic-containing (saturated) salt solution through a CST packed bed (at 5 cm/min. superficial velocity), or drying CST in air at 100 C for three days. Some tests occurred under 50 and 25 psig of argon. The following conclusions summarize the results. Pretreatment of IE-911 in organic-containing (e.g., tri-n-butyl phosphate, dibutylphosphate, butanol, paraffin and Dow Corning H-10 defoamer) simulated waste or simulated waste yielded a 83% slower rate of cesium adsorption and 56% lower cesium capacity after one week. Pretreatment of IE-911 in 2M caustic solution for 48 hours yielded a slower approach to equilibrium cesium distribution in batch contact tests--7.7 mL/(g*h) during the first 48 hours and 2.4 ml/(g*h) thereafter. Carboxylates and adsorbed carbonates inside the pores likely affect the cesium transport by either increasing the path-length or reducing mass transfer rate. Heating IE-911 as received from the vendor at 100 C for 24 hours significantly degraded its cesium removal performance by a 40.7% reduction in capacity and 43% reduction in sorption rate over one week of testing. Testing determined nearly identical distribution coefficients Kd between lot numbersign 9990-9681-0004 and 9990-9881-0005 (i.e., difference of only 5.6%). Tests measuring water insertion rates into IE-911 show that hydration of the IE-911 does not appear to limit the rate of cesium sorption. Increasing the atmospheric pressure from 0 to 50 psig had no effect on cesium sorption. Note that lower apparent